We can debate for a long time if other Lisps deserve the status of "true" lisp or that title forever belongs to Common Lisp only. There are many prominent Lispers that criticized Common Lisp for being overly bloated and for butchering the sole idea of Lisp. To be honest I do feel like agreeing with them and kinda glad that Common Lisp is dying. That is why I did not include CL in that list.
Unfortunately you are missing out on a lot of things Lisp has to offer, by working with non-core Lisp-variants. For example it would be clearer to you what interactive working with a Read-Eval-Print-Loop in Lisp actually can do - besides the simpler improvements in interactivity. There is a whole world of core Lisp which you are ignoring. You are also slightly misleading people by not mentioning core Lisp languages and language contributors to those.
> or that title forever belongs to Common Lisp only.
Emacs Lisp, Visual Lisp, ISLisp (an ISO standard), various Common Lisps and their variants, Interlisp, Portable Standard Lisp, ... and a bunch of others.
You are setting your focus on languages which are more or less derived from those (for a reason, often with specific improvements or alternative features), but missing out on the core language implementation features. All the above have LISP in their name, which Racket, Clojure, Clojurescript, Fennel, Chez don't. There must be a reason for that. ;-)
Take Clojure and ClojureScript. Without Common Lisp those would not exist. I can remember when Rich Hickey was an active Common Lisp user (he used LispWorks and we were on the same mailing lists). He developed stuff in Common Lisp, worked on Common Lisp to Java integration, wrote a first sketch of Clojure in Common Lisp and so on.
Luckily he was open minded, learned a lot and created a language (with lots of lessons from Common Lisp), which a lot of people like...
The language you wish is dying, was literally the one where Rich Hickey learned from..., like many people before and others, open minded, will also do in the future.
I don't want to criticize CL, but I feel today it's neither an introductory Lisp nor academical or pragmatic. I think advocating for Lisp by pushing newbies to CL, telling "that's the true Lisp, and others not so much" is damaging. Common Lisp today has become like a Latin of Lisps - knowing it is awesome, but practicality of that knowledge is quickly becoming irrelevant. Those who have zero exposure to Lisps can be easily intimidated by it.
My own opinion about CL (why I said "I'm kinda glad it's dying"), shaped through influence of other respectable Lispers quotes:
Guy L Steele notably criticized its standard for being over 1000 pages.
Daniel Weinreb criticized it for being Lisp2:
> ... It makes the language bigger, and that's bad in and of itself.
Richard Gabriel:
> “Common Lisp is a significantly ugly language. If Guy and I had been locked in a room, you can bet it wouldn't have turned out like that”
Paul Graham:
> A hacker's language needs powerful libraries and something to hack. Common Lisp has neither. A hacker's language is terse and hackable. Common Lisp is not.
The good news is, it's not Lisp that sucks, but Common Lisp.
> but practicality of that knowledge is quickly becoming irrelevant
just the opposite. When there is lots of interest in Lisp derived languages, the core language stays important, since it's the fountain for many ideas.
> through influence of other respectable Lispers quotes
But you ignore the context. The only real one critical about Common Lisp is Paul Graham, and he got rich and famous through a Common Lisp application: he wrote an online-store system in CLISP and wrote two books on CL, one of which is a real classic: On Lisp. But later he was critical and designed Arc as a very different take on Lisp: small language, small programs, small identifiers, for web programming. It's the one which was used to develop this website here on Hackernews.
Guy L Steele, Gabriel and Weinreb came actually out of a tradition where they used Lisp systems which were MUCH larger than Common Lisp. Steele literally worked two decades with and for Maclisp and Common Lisp. Steele wrote the first two defining books on CL. Steele also has a much larger scope: he worked on things like Scheme, High-Performance Fortran, Parallel Computing with the Connection Machine (which started out with a parallel Common Lisp), C, Java, Fortress, ...
Weinreb was working at Symbolics on and with Lisp Machine Lisp. He co-wrote one of the first object-oriented databases, in Common Lisp. Later he took those ideas to a C++ based OO-database. Years later Dan was back working with Common Lisp at ITA where he spent lots of time... I met him once in Hamburg at a Lisp meeting and he was happy then, working with SBCL and Clozure CL. Unfortunately he died much too soon.
Gabriel worked on the Common Lisp design. He also wrote a book on benchmarking Lisp. Then published a critical paper on Common Lisp and THEN founded a company which developed a wonderful implementation: Lucid CL. He also was then working on the CLOS standard proposal.
You are totally missing on the background and what these people actually were working on. Since the broader Lisp community is very diverse and always was, there were and are always critics in all directions. Some people think modern Lisp is too static, other think it is not static enough, some think it's too interactive, others think its not enough interactive... but you need to understand the context.
Steele, Weinreb and Gabriel were actually the first designers of Common Lisp - the so-called 'gang of five' included also Fahlman and Moon.
It's like claiming that Tolkien was critical of The Lord of the Rings, because it has too many pages, took too long to write it and there are lots of new fantasy books. Tolkien wrote that defining book - like Steele, Weinreb and Gabriel developed Common Lisp and Graham wrote a classic book on (Common) Lisp programming.
There are lots of other things in the Lisp history and I'm happy that some people work to preserve those ideas - not wishing to ignore it and that they are dying.
Okay, that is fair. I honestly appreciate you spending your time, convincing me. To be honest I did not need much convincing. I am sold on Lisp already and CL is just a matter of time for me, personally. But I still think it's not a good introductory Lisp for those who still need convincing. Maybe after using it a bit my opinion changes, but I know several former CL devs, they share the similar opinion.
Maybe somebody does it like Rich Hickey, coming from C++, checking out CL for some time and then moving on. But it transformed him. The next generation may look at Clojure, check it out some time and then move on to design the next thing... it might then be helpful to understand where SOME (by far not all) of the ideas originally were coming from...
Clojure has the 'half' of its features on the Java side. The whole package is a huge Java infrastructure with zillions of features + Clojure.
Common Lisp was designed to be that on its own, and its actually not that large anymore - compared to similar options.
Everyone who wants to learn a Lisp which stands on its own feets - for example SBCL has only a relatively small C core and all the rest is Lisp itself - should have a look. This has deep effects generally for Lisp: better error handling, better interactivity, images, simpler debugging, less language compromises on the low-level, ...
Lisp is also not opinionated. Working in a non-opinionated languages is different. In Lisp the developer may need to develop his/her own opinions.
Right now you are looking at a shallow image of Lisp.
