Yeah, they only have a finite number of servers that they can run VMs on, and are pretty consistently at max capacity. That said, there’s also limits on individual stream times, so after a certain amount of time you have to reconnect to continue playing (which, if you’re playing in a busy time, means re-queueing). So this at least keeps the line moving, in a way.
I haven’t tried it in a year or so, but when I played it last, I didn’t have very long lines; a minute at most, even at peak hours, on a free (deprioritized) account. Not the end of the world, but definitely an inconvenience.
I wonder if it’s a licensing thing. I know a few of these games had heavy use of licensed music, like Jet Set Radio and Crazy Taxy. At least, the original versions did, I’m not sure if that’s the case for the Steam ports.