It’s nothing new, but I see it happening right now. Spammers are searching for “leave a comment” on Google, and using those results to feed into spam bots that go and do the work. Google, please stop letting spammers search for “leave a comment”. Just block that string from being searched, as it won’t ever affect an actual user. Nobody would just be searching for “leave a comment” and not have malicious intentions.
Software doesn’t have insight like this, and that’s why programmers must remain in the business. To help the software learn.