I suspect that the increased number of ads is in response to the increased use of adblockers.
As for Youtube farming me for data they can sell or use to manipulate me, well, yes, they will do so as much as they can because that's the whole point of Google. That's what Google is for. However, I prefer not to make it easy for them. So I don't log into Google, which means I don't and won't have a Youtube Premium account. I don't have cookies that persist over sessions - all cookies are deleted when I close a browser or tab and all cookies are deleted during a session if they haven't been used for 30 seconds. I don't have DOM storage enabled, so they can't use that to track me. I use a VPN, so my easily viewable details vary from session to session and are fake anyway.
Judging by the videos Youtube recommends to me, it works. They're always related only to the videos I have watched that session, which implies that Youtube doesn't know who I am.
I also don't use an adblocker, as a deliberate choice. I do use security software that blocks almost all ads because they're served in an insecure way, but Youtube ads aren't. I could block them, but I choose not to as I consider it a fair price to pay for the content. I even let some of the ads play in full, if they're shorter than a minute.