There are a few ways in which bots can fail to get past such challenges, but the most durable one (ie. the one that you cannot work around by changing the scraper code) is that it simply makes it much more expensive to make a request.
Like spam, this kind of mass-scraping only works because the cost of sending/requesting is virtually zero. Any cost is going to be a massive increase compared to 'virtually zero', at the kind of scale they operate at, even if it would be small to a normal user.
Like spam, this kind of mass-scraping only works because the cost of sending/requesting is virtually zero. Any cost is going to be a massive increase compared to 'virtually zero', at the kind of scale they operate at, even if it would be small to a normal user.