Question

In what ways has GNU/Linux improved upon previous UNIXes/BSDs?

Answer 1

I don't think that GNU/Linux is so much an improvement as GNU/Linux/Open Source is the improvement. Commercial software, and Open Source has to keep from falling into this, is produced on a production schedule and trying to keep costs to a minimum. Open Source is people writing "The Great American Program", and then many other people reviewing it. This speaks to the quality of the code.

The same labor/cost differences encourage innovation.

Not having to sweat licensing is the icing on this cake.

All of this is wonderful, but it's also causing some, IMO, horrible things to happen like launchd and systemd.