After spending some months on Big Sewer & Monterey, I went back to Mojave on my 2019 iMac & decided that’s where it’s staying, bc it’s the last OS Apple made in which everything works (except screen sharing of course, bc that was broken after High Sierra & Apple just can’t afford to fix things like that with its limited resources.). Mojave runs fast and powerful, works with 32bit apps and more importantly drivers, so any piece of hardware on earth will work with it. It’s pretty much perfect. The iMac also stays offline so I don’t worry about security updates, like a working time capsule of peak Apple.
It does however mean that I have to/get to keep a 2015 MBP as its dedicated portable side, to complete its own ecosystem. Since Apple’s planned obsolescence model includes breaking file format compatibility between versions of their own software, it was a decision to use the pair of machines together locked in the Mojave era. The limitations are that I don’t use them for work or school things, just personal & home. Work requires online access, up to date security & software to be compat w everyone else, so I use a dedicated new machine for that. I questioned if it were really worth having an old outdated system when I need a new one anyway. But it’s very good to keep the personal separate from professional, and while the new machines are built to fail and disposable with their soldiered in SSD’s, the old will run indefinitely. 20 years from now I’ll have thrown half a dozen new computers in the landfill, while my 2 old personal machines, on their 4th SSDs & RAM will do everything as reliably as they ever did, and my 3d models & all their linked parameter databases and everything else I’ve ever made will all still work and work together. Mojave or bust.