I nuke my 2019 15” MBP every time I install a new macOS. After a full backup, I delete saved fingerprints, logout of iCloud/Messages/etc, reset SMC and NVRAM, boot new OS from bootable USB, partition/format drive and install everything fresh. I then import my music and email, reinstall apps. It’s a laborious process but I only do it once a year and I’ve never had any major problems or had to track down gremlins or incompatibilites.
Having said all that, 15.0 runs just as well or better than 11.0 thru 14.x.x. Animations seem no less snappy, all my VMs run well in Parallels, Affinity and Office apps are fine. I run in clamshell mode with a Brydge vertical stand and Brydge TB3 hub with a couple USB-A spinning drives, a SSD drive, SD card reader and DisplayPort running a 4K display with Logitech Brio 4K camera, Apple Trackpad, Magic Keyboard and Magic Mouse. No excessive fan noise unless I’m running 3 VMs or one Teams session (Teams sucks resources-wise). Still not as snappy as Mojave, which I keep on a bootable SSD.
I’m actually happy I’ve got three more years of support for my Intel Mac. This should get me far enough along that my workflow and reliance on some x86 stuff declines and I can line up for an M6 when the time comes.