Yep. You need to pay for the patent with certain codecs, that's why operating systems with a company behind them usually do not distribute them. Same with a few Linux distros, such as Fedora.
You can install them and the packages for your os are freely available. Just not from the company making the product in the fear of patent trolls.
Always have been. It's either included in licensing a software or operating systems. VLC ffmpeg and other open source software are a bit of a grey area since they don't make money from the software strictly speaking.
+1 VLC will dutifully try to play even corrupted to hell files that any other media player would just fail with some form of "can't play, file is corrupt"
VLC just managed to get some newer video files to play for me on a 10 year old tablet that wouldn't play them with it's included video player. It was also one of the only apps on the play store that would still work on that old tablet as well. It's been my go-to video player for years now, terrific software 🥂