Why does everyone expect everything to be free? I'd argue that while money's part of it, the more important aspect is friction.

Much of the time the internet is a platform for procrastination (he says, posting here while waiting for Vivado to do its thing!) - if I'm just idly reading a page or two and I'm interrupted by the need to create an account and worry about payment details then I'd have to be heavily invested in what I was reading to bother jumping through such hoops, instead of just going somewhere else.

I'd also argue that advertising itself isn't the problem - it's the fact that the goal of maximising returns for advertising spends incentivises sleazy behaviour (not just the tracking, but also obnoxious audio ads and videos that partially obscure the content the user's trying to read.)