It sucks because from a user perspective, macOS is not really getting meaningfully better—nor does it need to at any particular pace, given its age and maturity.

If anything, I would rather them stop doing stuff like replacing a rather idiosyncratic but well-understood System Preferences panel with a half baked replacement that goes against half the Mac HIG.

If dropping support for Intel Macs meant huge performance wins for ARM Macs, or freed up the team to work on huge OS improvement I could understand it, but neither of those things seems to be true.

A bunch of blobs go into OCLP, sometimes with no source, so I’m hesitant about it. Are there any projects to build everything from code that is public? (will have at least reduced hardware support though)

As the article notes, not all models have that option. 2017-or-later is the cutoff now I believe.

Sure, take the upgrade if you can though.