The way you write this suggests that for each engineer at Meta there are 15k other people who applied for the job and didn’t get it, so their ~40k engineers correspond to a pool of 600 million potential employees. This is obviously nonsense. There are a few ways to explain your number:
- the same unsuitable candidates apply many times. This is not so surprising: suitable candidates get jobs and so stop repeatedly applying
- perhaps many people can be hired for a single ‘open position’, eg perhaps one is ‘software engineer based at headquarters’
- if many applicants are from people who are grossly unsuitable, eg maybe you must demonstrate job applications to get some state unemployment assistance
- maybe Meta aren’t hiring much at the moment and so it is harder to get in than other companies that are hiring
- the number might be misremembered
The downside to applying is trivial so even if chances do seem low, it can still be reasonable to apply. I think the probabilities implied by the comment I’m replying to are so extreme that you should have some higher estimated success probability from also considering the chance that the comment above is misleading.
The thing one often sees about automated cv filtering systems is mostly widely-believed nonsense. It is a story that is told to job seekers to sell cv-optimisation services. That’s not to say automated filtering doesn’t exist – a simple case is filtering out candidates that were recently rejected – but I think even if a lot of people are filtered out, that doesn’t mean you will be.