go through your subscriptions and get rid of the channels you aren’t interested in anymore
export subs as .json and import them into Freetube for desktop pc and Newpipe for android. Invidious and piped instances such as vid.puffyan.us and piped.video also allow you to import subs. You can also import youtube subs into RSS feed readers.
go into your google account settings, nuke and turn off watch hiyostory, turn off targeted ads and anything else you see in there.
Repeat step 1 every so often and better curate your list of subs. Your feed only contains the videos you want to see first in formost and not what the algorithm wants you to see. When you do have to use youtube itself it will be limited in how much data it can collect off you.