If each job takes 30 minutes to apply to, that's 50 hours per week, assuming you don't stop to eat or rest. I think my average job application takes a little longer unless I fill it with bullshit answers.

That's assuming you're just filling applications. It doesn't include finding them. I think in the time I was unemployed I passed over a few hundred absolutely reprehensible and morally objectionable positions.

Why so much ghosting? My speculation is perverse incentives of the modern world. Recruiters and HR need to justify their ongoing existence so they open positions that don't need to get filled so they can spend time filtering candidates. Meanwhile, candidates need to turn to auto filling jobs because and bulk applying because there are so many of these ghost jobs that recruiters who do need people can't get matched up. This turns into a race to the bottom of automation and counter automation where everyone loses.