Considering the job description is unrelated to the company and the title, this is a scam post, not quite a "ghost job".

They're probably rapidly opening + closing new jobs to increase visibility, as matching models on job boards tend to prioritize new posts.

Back when H1B visas were new. Companies would post jobs they did not want to fill. The posting was to provide evidence that they could not find anyone who could do that job. Personally I have seen so many Microsoft listed jobs, that it seems impossible that they could have a layoff, unless of course ....

a lot of market forces that incentivize the wrong behavior.

your company raised a bunch of money during the ZIRP era, your company needs to hire a large amount of H1Bs, you're a founder of 3-5 person startup that's been default dead - but your ego won't allow you to shut down the company or make it a 'lifestyle' company that's not attractive to VCs + many other factors

that's how you end up with endless jobs on LinkedIn.

Indeed has better signals.

I suspect some companies do this to look healthy from outside.