It’s possible to disable history in YouTube’s settings. This will turn off algorithmic feed replacing it with a reverse chronological feed of channels you’re subscribed to.

There are YouTube settings that seem to get unset periodically. Even some that their documentations says should be sticky, like caption preferences.

Maybe yeah. Though I doubt they’d reset data collection settings like that.

They do. I am currently in a weird middle where I have personalization off but ads are shown based on "videos you watched recently".