It's not necessarily a lot of sites that block non-popular bots - but often it's big sites (i.e. content-centric sites such as Social Media). Think Yelp, Twitte

It's not necessarily a lot of sites that block non-popular bots - but often it's big sites (i.e. content-centric sites such as Social Media). Think Yelp, Twitter, LinkedIn, Instagram, etc. That can add up to a serious percentage of the web.