> partly because it causes annoying delays for those trying to get to the site
This is true but usually a small issue. It’s further alleviated by cached tokens so you only have to solve the challenge once in a while per site, and a login token may let you skip it.
> partly because it seems inevitable that the scrapers will eventually find their way around it…A proof-of-work requirement is not a huge obstacle when you have millions of other people's machines to do the work on.
> partly because it causes annoying delays for those trying to get to the site
This is true but usually a small issue. It’s further alleviated by cached tokens so you only have to solve the challenge once in a while per site, and a login token may let you skip it.
> partly because it seems inevitable that the scrapers will eventually find their way around it…A proof-of-work requirement is not a huge obstacle when you have millions of other people's machines to do the work on.
Solved by making money off it.