I know a lot of Mac users who need to stay on Mojave because of the hardware/software they are using. Often very expensive hardware. I bet some will be tricked now into installing Catalina. Going back to Mojave is not an easy task for less savy Mac users. I think this is a very bad move which will lead to a lot of cursing.
In my opinion it's time for a boring LTS (long term support) branch of macOS that breaks less stuff. I really don't care so much for all the fancy features Apple has been working on the last couple of years (Handoff, Continuity, Siri). What I need is rock solid OS with a decent Mail client and Photos management sofware. It would also be nice if the built in apps would not randlomly delete my file between updates.
Rule number one of OS and application development; new features mean nothing if it isn't stable.
That is similar to a doctor's oath of first doing no harm.
I bought a MacPro 2013 and immediately let it upgrade. DOH!!!!!!
The pain in rolling back to Mojave because my AVID software did not support Catalina...
I always stay a Major release of OS behind. I let all everyone else alpha and beta the OS until the next major release, then I move.
In the case of Mojave; I will not be moving until I find a replacement for lots of software.
But there is hope. I read an article that shows you can run Mojave in a VM.
I already run CentOS in a VM.
What's one more VM on my server......