No, relevant ads based on the content of the page, not based on your browsing behaviour.

Google Ads based on browsing behaviour only try to sell you stuff that you already bought and no longer need. By the point the ad shows you graphics cards, like for me right now, I already bought one. When I was searching for one, the ads were showing me crayola crayons instead.

Make relevant ads based on what the person needs right now. No need for cookies or any tracking.

No! If the OP is on a "Let's play" video, a relevant ad is about a similar video game, computer hardware, etc. The version of "relevant ads" is a tracked ads, where he would see a sex toy ad on the video because he looked for sex toys the day before. But that is not a relevant ad to the content consumed.