2020 MBP - Want my old performance back :)

[WhatAmI]

So, back in 2020 this MBP was a huge upgrade from my old Air. I couldn't believe the snappiness but needless to say, moving from BigSur up to now Sonoma makes it feel really sluggish.

I've uninstalled stuff which isn't needed, cleared SMC/NVRAM etc, regularly run cleanmymac, closed apps etc but when opening up the lid it takes like 3 seconds to show login, apps take forever to load, you know the feeling.

Would a complete reinstall offer me any boost at all, or would I need to downgrade to Monterey/Ventura for this to be noticeable?

TIA!

 

[StoneJack]

I suggest complete erase and reinstall and maybe Ventura for that notebook (Monterey would be best)

 

[kitKAC]

I have a 2018 Intel running Sonoma and it's absolutely fine. Just Erase all contents and settings and set it up again.

 

[bousozoku]

You might try using the utility Onyx to clean out leftover logs and such, rather than start over again.