YouTube has had ads for longer than I’ve been using it. They introduced it in 2007 from a quick google search. I started using chrome in 2009, and Adblock extensions not too long after.
I’ve been here the whole time and I’ve known that ads were a way to monetize the video, but I blocked them because I don’t like ads. For a while it just seemed like Google didn’t care. I just did it because I could and there was no alternative. When they released premium , I went that route. I use and depend on the service for a lot , so I don’t mind kicking them some funds.
But please do continue expecting something for free despite the fact you have an option to watch it for free with ads or to pay for premium because that’s how it always was 🙄