Probably, but while I can't say it hasn't happened it's certainly not common. I don't have a count but I know I have a handful of stuff that were pulled years ago. Alot of it is tedious rights crap with music and the like which makes them ineligible for sale.

I imagine in the case of steam, there's not much reason to give a crap. They're not paying to store the files. Plus, while we all have known the days of "purchased" content being stripped were coming, who wants to be the company to really pop that lid?

Now that a few companies have broached the policy maybe we'll see more of it in the gaming space, but idk letting steam hold onto a copy of game files is also less of an "investment" than storing something locally and streaming it.