I don't think they are blocking based on browser. They are probably on another push. I'm getting "Ad blockers violate YouTube's Terms of Service" on lastest Firefox and uBO. I'm in Australia.
Using duckduckgo video search opens the video on the search results page, playing there plays without ads, I get the “sign in to confirm you’re not a bot” message sometimes though.
<a href="https://freetubeapp.io/" rel="nofollow">https://freetubeapp.io/</a><p>^ great alternative to youtube in a browser