Then I'll get ready to get off the internet. Most of the internet is already unusable without allowing metric tons of questionable JavaScript. And to be honest, I'm not missing out on anything by not going to those places.
Any service willing to be that user hostile will already be telling people they can only view content in the app. IE stuff you can comfortably live without.
Honestly, that might be a good thing. Make the web too painful to use (with some cookie popups we are almost there) and I might spend my time doing more productive things.
If that's a thing, I'll just end up treating them the same way I do now with sites who don't make GDPR consent easy to deny : blacklist them forever regardless of content.
TL;DR: Router-based blocking is fairly effective for now, but not guaranteed.
Host-based adblocking works if advertising delivery comes from servers distinct from content, and is delivered directly to the client (that is, the end-user's web browser) rather than "rendered" on the server side.
There are reasons the independent ad hosting solution's come about, not a few of which revolve around measurement and fraud --- a freestanding ad infrastructure gives metrics independent of the ads venue. In a world in which trustworthy data are hard to come by, this had been strongly embraced.
The rise and success of host-based adblocking creates an evolutionary arms race between advertisers and ads-averse publics. There are several possible countermeasures:
- Advertising can be intermixed with content, either with ads coming from content servers, or content coming from ads servers.
- Ad payload and content bait can be pre-rendered on the content delivery site. The user no longer has a separately-identifiable data stream to discriminate the advertising content.
There are other adblocking methods. Some rely on determining what parts of a web page (the "DOM", or document object model) correspond to advertising. Typically, dimensions (ads are sold in standard sizes), element names (usually HTML attributes including CSS class and ID values), or display attributes (fixed or floating elements especially) are used. The story's complicated. Browser-based adblocking typically includes several of these heuristics, in addition to host-based blocking.
And there are new technologies which will make even those methods less effective. (Look up direct canvas rendering as a leading option.)
Router-based blocking is virtually always to determining the source of a data stream, but not its content (thanks in part to the security and encryption now part of most Web traffic, thanks to HTTPS and SSL/TLS security protocols). PiHole and its equivalents have been largely effective to date, but still leak some ads, and may be less effective in future.