I always do a
clean install of a major osx update.
It's a drag to then install everything from scratch, but i think it's totally worth it.
And to be honest, it's not a drag for me personally, i'm just a guy that loves
re-installing everything nice and clean, it gives me major feelings of happiness
So i did also a clean install of Sierra, some time ago. (macbook retina 2015).
Re-installed all apps and plugins from scratch.
Takes forever to come to the point that you have everything installed.
Again, no problem for me.
The "smoothness", stability, and snappiness of such a fresh installed system is amazing.
I have literally zero issues (be it audio & non audio apps related) on this system and it just flies.
Reaper's running just beautifully, other DAW's i have also.
In the more than 15 years using this clean install method, i can't say that i ever got any serious issues on osx.
I was always quite stunned reading about many people having major issues on OSX, in all sorts.
Turned out the majority had done a upgrade, not a clean install.
Maybe i have just been very lucky for the past 15 years.
Then again, i always kiss my mac goodnight when i go to sleep, maybe that helped.
Cause i am still in love with Apple, after all these years.