The document you posted (which is very nice BTW) indexes all the existing valves so it makes IMHO the (actually problematic) situation seem worse than it is (because the actual diffusion of this or that type of valve isn't taken into consideration).
basically all M30x1.5 are not listed as they are directly compatible.
Then, 11 most common types are listed, and for the first 6 ones (the most common among the non-M30x1.5) the adapter is included.
From personal experience (anecdata, so take it with a grain of salt) the "standard" M30x1.5 + Danfoss + Giacomini + Caleffi cover really nearly 100% of what people can find in their home.
These other guys here say that a basic set of adapters cover 90%:
The only way is to change the valve (very expensive) our buy extra adapters. This is also true if you break an existing thermostat: You can't purchase them anymore. You'll have to buy one of the "new" standard and pick on of the "solutions" mentioned above.
For example I'm living in an early-1990s building equipped with the old Oventrop M 30 x 1.0. I just bought a smart thermostat which claims to be compatbile with Oventrop but turned out only with the post 1998 Oventrop M 30 x 1.5 …
For example, in the 90's the design for rollerblade frames (the part for the wheels attached to the boot) were all over the place, but then a few skate manufacturers agreed on a single design called the Universal Frame System. As soon as it was adopted, it unleashed a whole bunch of innovation in boots, wheels, liners, etc, because suddenly you don't have to fuss over on particular part and can then spend that energy on smaller, more interesting innovations in the rest of the product. Like suspension in the frames!
I think it is a case of “he who pays the piper calls the tune” .
What about the reverse?
Given the low price of each radiator controller, the engineering is top-notch. Mesh network works all of the time, the batteries last for multiple years and the installation is relatively painless.
This is one of the few IoT solutions that 'do-not-suck'. No calling-home to China, no unexpected updates and upgrades, no complicated install process.
 Openhab Website https://www.openhab.org/
I didn't switch to OpenHAB though, but instead hacked their original desktop control software, which is actually a Java web app with a localhost-bound Tomcat, to make it runnable on a headless Linux box and bind to the LAN IP. This way I have their control panel available constantly and remotely. Works surprisingly well and stable, given that this mode of operation was never intended.
Their actually-intended remote control path (via a server provided by the manufacturer) is crap however, very slow reaction time, unreliable and you somehow have to pay a subscription after a trial period.
Our current system works using a CalDAV calendar with repeating appointments providing information about work/home/sleep times. This is combined with presence detection using our mobile phones and Z-Wave motion detectors. This also controls lights, light color temperature and our ventilation system. All events go to InfluxDB / Grafana combo. OpenHAB 2 is the spider in this web of IoT stuff.
Replacing the knob is a safe operation that cannot leak water. I could do that on all radiators in a flat without ever running the risk of causing a leak. Replacing the valve would require opening the water circuit, thus you'd first need to turn of pressure, which may or may not be possible (think: apartment building). Replacing the valve may also not be allowed for people that rent a flat.
De/re-pressurising your central heating system and physically replacing all the valves is a task that's going to require specialist tools and probably a plumber. It's also pointless, as there's basically only one standard, so you'd have nothing to replace them with. Replacing the knobs on top is a case of watching a youtube video and spending two minutes with a screwdriver - which is the intent of the design.
What you're saying is broadly comparable to "why would you buy smart lightbulbs when you can just replace the entire light fitting and all the switches in your home?" - except I'd argue that's actually easier for the layman than messing with radiators.
After all, if you're selling a £150 smart home system, but 80% of buyers need a £150 professional installation, the cost will deter a lot of customers; and for those customers who value your system at £300, you're missing out on capturing a lot of that value.
Every facility above a certain size will have a few modified parts that were created (not necessarily with a mill, often with hand tools) and installed over the years to meet various needs.
Edit: Lol, why is this down-voted? Encountering modified parts is like a weekly occurrence depending on the age of the systems you're working on. Ask the maintenance dept. at your local community college if you don't believe me.
You are responding with snark, on a topic on adapters for use in homes, with solutions that you yourself say are for "facilities above a certain size".
Your post is off-topic, but you might very well have been upvoted if you had presented it in a more positive way, like talking about your prior experience machining valves for your own heating system. That would have been interesting.