2000 testers isn't unreasonable.
There are over 4 million of software engineers in the United States alone, and I'd wager that many of them are capable of doing QA. Apple is a company that is able to pay competitive wages for their talent.
Most reviews are for minor app updates. "Bug fixes and performance improvements." Ho hum. Twitter and many other companies release app updates every week, just because they can.
I suspect the job of app reviewer has a pretty high turnover.
That's cool, but testing roles exist throughout the industry and some people choose QA as a career.
I wouldn't want to be an IT support specialist, it sounds like a boring job to me, but that doesn't mean that there aren't a million career support specialists employed by trillion dollar companies like Apple.
I'm sure people would line up to be paid well to work on Apple's QA even if you wouldn't.
I don’t enjoy doing this job so I won’t do it.
I don’t think that’s true for the majority of people, who just happen to do a specific job because they’ve been trained for it and it pays the bills.
I'm also a dev and have had the chance to work with top notch QA testers. A good QA engineer is a blessing. Unfortunately that is not what an apple app reviewer does. Their work is much more boring.
Are those people even out there and available?
I mean, maybe there are right now because of Great Depression II, but were they available from 2008 to 2019?
As a company, Apple is generally against remote work, with only grudging exceptions, so that's another issue in hiring.