Its not a legal question but a behavior and sustainability question. If it is fair use, but is undesirable for content makers, then they’re still not under any obligation to allow scraping. So they’ll try stuff like this, and other more restrictive bot blockers.

Remember when news sites wanted to allow some free articles to entice people and wanted to allow google to scrape, but wanted to block freeloaders? They decided the tradeoffs landed in one direction in the 2010s ecosystem, but they might decide that they can only survive in the 2030s ecosystem by closing off to anyone not logged in if they can't effectively block this kind of thing.