The article admits this, but then simultaneously tries to claim that the loss of caching would prevent that from being common... but this loses caching.
I can already give everyone unique resources for the same URL by keying the response on the Referer (which I would also add to the Vary header).
The article also admits this, but then tries to claim problems that are out of scope... the "first visit" will never be to a subresource of a page.
The article further tries to claim that this is difficult or defeats caching, but adding Referer to Vary is trivial and works with all CDNs and caches.
Meanwhile, if we believe this kind of argument about "people won't bother to do it because it is slightly hard" (I don't), then we need to be consistent.
It will take work to generate the multiple obfuscated copies of this bundle and be maximally disadvantageous to caching to do so for each visitor.
Ad blockers that work using URLs are fundamentally only possible because they aren't common: if you make them common, they will break.
I mean, ad blockers are so uncommon right now that you can often get away with blocking hosts at the DNS level... that is so trivially defeated!
If you want to do something useful, work on post-download ad "view" blocking by having an AI classify regions of the page as ads and then erase them.
This is also an arms war, but it is one that will more than likely at least result in subtle ads that you don't mind (as the AI "lets them slide") ;P.