It logically follows that the same measurements could have been made by tracking events on the server, possibly without involving additional client side scripts at all. No, it wouldn't be as easy or allow tracking everything the user does down to the pixel, but that's not the adblock enlightened user's problem...
It is my understanding the industry is moving towards server side "tagging" to improve performance and probably also to try and obfuscate it from ad blockers. But I haven't paid much attention to that.
That won't tell you how many didn't see the page or converted though.
Isn't that just the ecosystem provided by the Big Tech ad platforms? Publishers at some point very much wanted to sell ads directly as the CPMs were 10x of what they are now. Then FB and Google took over as the middlemen, pushed CPMs down, added sophisticated targeting and set the precedence for how things are implemented.
Sure the tech giants could team up with the publishers to take back control but they'd need to share more of their revenue in exchange which I am doubtful they'd go for. Not just because it means losing control but also it creates the hassle of having to deal with a fractured landscape of publishers of very varying technical acumen.
I don't think that's true at all. Clients can not prevent measurement through server side logs. Publishers have just decided to put all their eggs in one basket by deploying a bunch of trivially bypassed JavaScript adtech trackers, and now it has come back to bite them.