(I've had great results for a site like this using Gatsby + Netlify)
It can’t be legal to run a user-agent in your computer, and illegal to run a user agent in the cloud. The question becomes, what is the defining property of a user agent?
I think the way to think about this is to compare it to magazines. While you can say that it's morally unjustifiable that magazines has ads and filler pages because it'll use more paper and we need to use less paper, the argument on the other side is that the business has to survive too so ads and trackers makes that more likely (from their perspective, I don't necessarily agree with that)
When you think about it this way it’s clearly fair use.
Such gotchas don't work in law in general (in my very limited experience).
But in this case, the intent is to show the full article without anything else, so most likely copyright infringement.
Stretching the definition of "fair use" is a favorite internet past time. People have gotten pretty good at it. It isn't anywhere near as flexible as people seem to think, and I mean, like, by a couple orders of magnitude. This particular example isn't even close, honestly.
>Stretching the definition of "fair use" is a favorite internet past time.
Absolutely! It's really enjoyabe.
Basically, if you take the four criteria for something being fair use [1] in the US, which isn't the end-all, be-all of analysis but is a darned good start, this absolutely faceplants on all four. (And while it is technically up to the discretion of the judge, I'd say it's closer to an "AND" than an "OR" on the 4 criteria. You really, really don't want to be standing in front of a judge solid on only one out of four. This is to preclude the usual arguing about #1; even if I grant it, which I don't, it really isn't enough on its own.)
https://en.wikipedia.org/wiki/Folsom_v._Marsh
Anyway, courts have seen more outlandish claims - and gone with them (Oracle v Google), so whatever.
I think that the mention of DMCA [down thread] doesn't really work here, that's for sites with primarily legitimate use; if the site in question has a route for acquiring permissions, and has a system to check with users before they (the website service's commuters) download content - to check they have a license - then safe harbor provisions could apply.
Even torrent sites, I gather, tell you not to put up copyright content before giving the opportunity to do so.
All that aside, such sites are definitely copyright infringement in the UK (but I don't now how jurisdiction applies over the internet; I've yet to find good sources on that).