Games are bundles of licenses themselves. That music costs money, as do other assets and sometimes engines. And over time some of those licenses can expire or require renegotiation. Sometimes it's easier to just stop selling something than figure all that out.

Massive issue with a game like NFSU2 is all the licensed music. I just watched a video (https://www.youtube.com/watch?v=QGdLZTgMDd4&t=735s) of an EA producer working on bringing back old games, and he said it took them over a year just to get the music licenses for a 30 year old game. And that's if they can get the licenses. Famously, no one really knows who owns the game No One Lives Forever, and the supposed rights holders aren't particularly interested in digging through their pre-digital legal archives to try to find the required documents that assert those rights.

Because this is a billion dollar corporation and those typically hire cutthroat teams that negotiate with other cutthroat companies. I recently tried licensing a 50-year-old unaired raw video from a news corporation. It's in the range of $5-10k. We're talking b-roll with dead air and such.. big companies aren't interested in this stuff