This is already how it's generally done on Android (via hosts file.) Still detectable though: You can detect broken images on the page for example, which would tell you that the hosts have been blocked.
I would imagine that the cost of a false positive if something goes wrong with the ad network would be pretty damaging.
I don't know if it's still the case but Comedy Central's video player was atrocious, the video wouldn't play unless it successfully played an ad but ads just straight up failed to load 30/40% of the time so you had to refresh, watch an ad to get to the video controls, scan back to your place, watch another ad because you crossed a 'commercial break' point, have that fail 10 minutes later, and repeat. The whole experience was awful and lead to me just scraping the site for the direct steam link and eventually just deciding that Jon Stewart wasn't worth it.
Pretty much exactly my experience with CC, and that despite being a strong admirer of Stewart.
HBO is following a vastly saner path with John Oliver, whose videos simply appear on YouTube. I'm not generally a fan of single-vendor consolidation, but if:
1. Video providers aren't going to directly provide media and...
2. YouTube Just Works (including via scrapers such as youtube-dl), well, then so it goes.
NB: ytdl also hits a ton of other sites, including Vimeo and The Internet Archive (which, truth told supports direct download and streaming, but ytdl is in finger memory now). Those that Just Work will be utilised.
I've block ads with a host file on PC for 10 years. Maybe it's my browsing habits, but I can count the number of times it affected my ability to browse content on one hand. I also manually add a lot of the entries so imagine that also helps.
Ah I'm glad to find out it wasn't just me that suffered through this. Actually I genuinely wouldn't have minded so much, if it wasn't exactly the same ads day after day. I can recite that new Comedy Central App advert word-for-word (complete with everything each comedian says - "This is the height of luxury!", "Uh-oh ha-ha", "Give it to me", "VISIT ME!" etc)
I guess you could have something that makes it still successfully retrieve a working image, just not the actual ad maybe?
I guess then an ad-versary could check if the images are signed or w/e?
