I imagine they're just looking for any low-hanging fruit where they can script something to maybe make a buck or two. It's the forum equivalent of someone calling you up and saying they're from Microsoft and your computer is compromised!!! Like, 99% of everyone won't fall for it, but whoever does click through and buy something will offset the minimal investment by a substantial amount.

Not directly related but Reply All had an amazing podcast about Indian tech support scammers where their investigation just goes totally off the rails:
https://gimletmedia.com/shows/reply-all/6nh3wk/