[PaulDavisThe1st]

I would say that there is no longer a viable GM-like concept.

Take a look at the libraries released by Spitfire Audio. You won't find anything remotely like a GM-style collection.

There's a buzz word of the day - "cinematic" - that has been defining new sample library releases for a while now. They are definitely not focused on "here's a sort of complete set of sounds corresponding to traditional instruments".

People generally want more unique sounds. Maybe a GM bank is a good starting point for people who will work with fairly traditional instrumentation (even they eventually switch away from the GM bank itself). But it's not much use for people wanting more distinctive timbres and textures, and for "cinematic" work (read: games, films, soundscapes), that's normally the goal. It's also where, for now, the money is.