Help! After updating to Sonoma, my MacBook Pro (2015, 13 inch, i7, 16GB RAM, 1TB SSD) ran impossibly slow* - so I reverted root patches with the intention of reinstalling them - but now patch reinstall is failing completely. Any ideas how to fix? Thanks!

*After updating to Sonoma 14.8.7 It would boot up fine, but opening, closing and dragging windows was so slow it was unusable - even with Reduce Transparency and Reduce Motion switched on, and the Wallpaper switched to a static image. I have Automatic Software Update switched to off.