I was at my parents this week and my dad said his tablet got slow.
I checked the running apps and open tabs and the phone couldn't even express it in a number (normally it does up to 999).
Then I hit the clear background apps button and the thing just straight up spazed straight to a full cold boot.
An hour later, dad said it was much much faster now, but that I "removed his apps". (I didn't and they were still there, just not running all the time!)