You should be a able to change how URLs work for your own website. They're not making any promise of stability here.
I'm allowed to move my arms like I want, but that doesn't give me the right to push people off cliffs.
In both cases, sites are attempting to tie content consumption to content monetization, and users are attempting to get the content without the monetization because they dislike side effects of the monetization.
It's also further defending hostile dark patterns and evading explicitly expressed personal intent.
The browser is a user agent, not a publisher or advertiser agent.
The will of the (informed) visitor doesn’t matter when they are visiting a place. I can’t have an intention to take a painting from a museum, ranging about the museum making it hard