But I just checked, and it’s available now. (Not squatted.)
I think some people run systems to buy up domains that expire, in case the expiration is a mistake. Then they can make a few bucks selling the domain back to the dummy who let it expire accidentally.
There’s a limit to how much you can make doing this, though, as any big company probably has a trademark on their domain. And if they do, they can just ask ICANN to seize it from you.
I think that’s different from someone who registered a common word (or many) and holds onto them, hoping to sell them to people who want them.
The domain squatting business is kind of like poker. You have a slow bleed of costs from annual domain fees (the ante in poker) and few deals to offset that (winning a hand in poker). Over time you have to either score some big deals, or eventually cut your costs. This limits the utility of squatting random nonsense domains for very long.