The YouTube alternative app Vanced was discontinued a while ago due to the takedown notice the developer received. I don't watch that much YouTube, but when I did the modified client was what I used. Not only because it blocked ads from YouTube but it also includes many other enchantments compared to the official app.
Today the app finally stopped working due to some update. I had to resort to the official app to access the videos I was looking for. The experience with all those additional features replaced by adds was horrible. I'm sure they just want everybody to use their premium subscription, but the experience so far was so bad I don't even want to try it out for free.
Another place where I've started to see ads is Prime video. And that is a service I'm already paying for! I've hear Netflix is also testing ads in their service, although they plan to have a separate ad supported plan and not show them to the normal subscribers.
I've tried to block as many ads from my life as possible. Pi-hole, ublock and a sticker in our mailbox have been working relatively well beyond the services I'm willing to pay premium to get the ads removed. But it seems advertisers and content providers are constantly pushing those ads in new ways to us in am increasingly annoying ways.