I looked this up and realised it’s the page I’d seen briefly on a range of websites lately. It’s not annoyed me at all. Not nearly as much as having to complete captchas with slow refreshing tiles.
I don't think you'll find an article by Google saying "yes, we sometimes completely block users while making it look like they're not blocked and wasting their time".
Google also prefers if you have a Google account logged in.
reason why is 1. Google and others really needed the training data, and 2. it probably helped justify the cost of providing the captcha service for free worldwide (old free tier was 1M/mo)