The problem is the assumption of a "simple RPC" protocol... there is no such thing. There are network issues, proxy errors, and two-sided race conditions that complicate any network related code. Network programming is distributed programming, which is not easy. RPC protocols try to mask that difficulty, but more often than not they sweep it under the rug.
RPCs make it easy to get started on a dev machine. making network calls appear like function calls definitely speeds things up when the network is working perfectly, but it papers over the complexities of debugging network issues and complex distributed race conditions, which will inevitably come up later.
Being explicit with network communication has its benefits.
(corollary: for the same reason as above, I don't like lazy evaluation of database queries that exist in many languages. When you hit a database, it should be intentional, you should know about it, and should properly prepare for any necessary network issues, caching, and cursors. Many modern web frameworks gloss over this).
I don't see how those things are really solved with rest, particularly given that people will often be using a wrapper rather than building their URLs manually everywhere.
Definitely not "solved", just made more explicit, kind of like a warning sign in the road. A while ago I worked with an RPC system where the RPC calls looked just like normal function calls... everything worked well, until it didn't.
Anytime a computer program consumes a potentially scarce resource (e.g., network, disk, database, etc), there should be some warning-sign or flag raised to the developer. RPC hides that, whereas REST makes it more explicit. So much of programming is social, and the mechanics of REST, even though theoretically identical to RPC, raise many social flags warning of danger ahead.
Or in other words, there is absolutely no technical justification for using this overly verbose and unmaintainable mess. It's just some vague philosophical thing that has no clear benefits. Like OOP.
I doubt that these qualities are actually achieved. Generally I don't think there have been many (if any) languages where excessive verbosity built in to the language has proven to be a good idea. Think COBOL, Java...
It's worse if not only statements are longer, but you are actually forced to treat similar things in very different ways (like URL resource vs query string vs post parameters). It just increases code complexity without any clear benefit.
I'm not really sure I see the difference. One of the first things done is to wrap all the calls to the webservice in some kind of API (often using a pre-existing library), which puts you back exactly where you were with calling a function which happens to make a web request.
RPCs make it easy to get started on a dev machine. making network calls appear like function calls definitely speeds things up when the network is working perfectly, but it papers over the complexities of debugging network issues and complex distributed race conditions, which will inevitably come up later.
Being explicit with network communication has its benefits.
(corollary: for the same reason as above, I don't like lazy evaluation of database queries that exist in many languages. When you hit a database, it should be intentional, you should know about it, and should properly prepare for any necessary network issues, caching, and cursors. Many modern web frameworks gloss over this).