The main issue is not with the software manufacturers but with the Graphic Card Developers. Maxon etc.. will develop their product on the most up-to-date versions, (they have to).
The Graphic Card developers will update their drivers to meet the latest specifications. However, after spending daft money on a card that resembles a skateboard they don’t keep the driver compatible with the original driver. Surely a developer can code a driver to look at the environment it is working in and switch to a compatible code. Simply meaning, when you buy a Graphics card, the driver should be stored in ROM, any updates will be stored in EPROM giving the card the ability to switch to suite it’s working environment.
I built a PC many years ago to run OSX. After spending daft money on a Graphics Card, it was amazing in C4D only to find that because the card did not support CUDA all my Adobe stuff was useless.
I just see it all as a money scam.
My biggest hate right now is dam render engines. Just seems like everyone has to be on the same render, which means everyone has to have Redshift etc. to have complete compatibility across the Graphic Production Community.
To answer the original question about C4D Versions. I love R18, does exactly what it is told, I only use R23 for some stuff and bring it in to R18.
My setup is so simple; iMac (27-inch, Late 2013), I love this computer. No crashes again does what I ask of it. My render computer is PC Thread Ripper.
May not be the best setup, However, no headaches, no stress and the job will be done when it is done because I like to sleep at night. The all nighters are well behind me now!
BTW I’. Waiting on Apple releasing the new 27” or maybe 30” M1 or even M2.