From my experience this is one of the ways it might work.

Recruiting (company's internal function, which is part of HR) is tasked with soliciting profiles to see what's available on the market. There's no real position but the recruiter(s) invent one according to what the business told them they would eventually need. There's no hiring manager behind it (as there's no position to be be filled). Recruiter either periodically meets with the business group that requested the research or prepares a report on the results (number of resumes that came in, salary requirements, etc) and presents to the business group that requested it.

So there's a reason these resumes are being solicited, it's just the reason is not to hire somebody. Sometimes it is done to justify business decision (ie to move to a different technology, or to expand to a new geographical area). Sometimes the business group _might_ be willing to open a new req if "the right candidate" comes up, but it's not guaranteed.

It also allows HR and recruiting to justify their presence (they are busy despite the fact that the company might not be hiring at all currently).

So there's reasons why these positions are posted and virtually none to prevent the company from doing that.

1. With the current AI bots, likely not. And that basically shows how inefficient these systems currently are.

2. The hiring manager does. The bot certainly does not. The odds of someone able to please the latter while meeting the former is low odds, for a candidate that's already low odds to begin with.

3. Not impossible. And that's all the justification they need as long as they aren't penalized for what basically a ghost job.

I think the answers to these is usually no, but there's one (questionable) person in leadership who's like "what if somebody from Google applies?" (or whatever equivalent). Never seen it work. Encountered it a few times. It tends to be magical thinking embellished by narratives around 10x engineers.

"what if somebody from Google applies"

I'd be immediately suspicious. Why are they leaving Google to come here?

I mean, Google laid off how many employees these past few years? Nearly million?

I do hate this stigma that clearly being laid of means you're a lesser programmer.

I did get hired like that once. Small company with just 3 other employees not really interested in hiring, but I had some useful experience in their domain so they decided to hire me anyway (and then went bankrupt a few months later, but they probably would have happened anyway).