> Have there been commercially successful free software games?
Going by https://en.wikipedia.org/wiki/List_of_open-source_video_game... , yes, although probably not to any helpful extent (and some of those are FOSS now, but weren't when released).
2048 had in-game ads that you could buy your way out of. You couldn't just install the ad-free version, because iOS is locked down. You could on Android, but not everyone is tech-savvy enough to actually do that.
Oh yes, I know open source games existed, but did any raise enough to pay wages of a team?
ps. I personally played Threes first, which 2048 copied without the style and made free. I admit I was slightly disappointed for the original devs that the copy became significantly more well known. It wouldn't be my first example of the benefits of open source.