It’s a shortcut for experience, but you lose a lot of the tools you get with experience. If I were early in my career I’d be very hesitant relying on it as its a fragile ecosystem right now that might disappear, in the same way that you want to avoid tying your skills to a single companies product. In my workflow it slows me down because the answers I get are often average or wrong, it’s never “I’d never thought of doing it that way!” levels of amazing.
Absolutely ran into fake CVs and people farming off the interview to 3rd party interview factories. Not at all surprised this was happening. Can’t say I ran into North Koreans but a lot of recruitment agencies were passing people on with little to no vetting. You’d interview someone on camera and they’d be a different person once everything was signed. Given how hard it was to correct that they’d still walk away with a few weeks salary, even in your states with at will contracts it’s super difficult to let anyone go.