No it doesn't, as I have tested videos are delivered using rX---sn-cnoa-cage.googlevideo.com blocking these will prevent videos from loading. Also these are region specific (in my case India). Also ad domains have some sort of commonality, for example I get ads from rX---sn-h557sn7r.googlevideo.com and from 6 other domains, so I blacklisted from r1 to r20 for each domain. I haven't seen any ads from a couple of days.