I litteraly havent seen an ad for like a year now, i use brave browser on mobile and desktop wich has a built in ad blocker, on mobile i have newpipe wich is a privacy focused youtube client, no ads as well. Im not on mainstream social media so i dont see ads there either. 

 I use Brave everywhere else, but the YouTube app on Apple TV leaves no clear options to avoid them unfortunately. 

 Use your tv as a desktop display then. Idk if it would work on apple TVs but i do it 

 Simplest option is to pay for Premium (it’s worth it for me as I use YouTube music) but goes against the grain..