I run what's called a "honeypot," which is part of a volunteer cybersecurity network among web administrators. Unless you run or maintain a server, you can't really appreciate the number of attacks on a system.
A decade ago they would simply scarf up any email addresses they could find and you'd end up with an inbox full of spam, but spam blockers made that ineffective so now they crawl the web looking for anything that has a login, online shopping cart, or something that requires your input, and flood it with web links to various sites, mostly porn. I think a lot of overseas porn sites pay people to draw in traffic.
As annoying as they are, the "are you human" boxes are designed to protect the system you're accessing, and the fact that you see them much more often is an indication as to how many sites get attacked on a regular basis. It's also a protection for you, because a single link that you may find interesting could land you on some malicious code, ransomware, or spyware.
What's bothersome about it for me is I generally have to go through the links to determine whether the site is harmful or not, so I may have to solve anywhere between 100 to 200 of those in a day. The other one is the "horny women" one which was probably misconstrued and I should have elaborated more on at the time, but I've gone through 300 to 400 of those on some days. The code is obfuscated so the process can't be automated. I have to manually go through each one.
If you have an ad blocker on your browser that blocks various sites, or you get a "this site may cause harm to your computer" message, that's from data we collect with a honeypot. Eventually the "are you human" boxes will be replaced with something better but for now it's a fact of life and that's why you keep getting them.