At least in terms of gaming I think multi-core CPUs killed them. A big argument for sound cards used to be that they'd give you higher quality audio and use less CPU. I can remember benchmarks from the mid 2000s showing less CPU usage with a dedicated sound card vs onboard sound. But by the time you get to the early 2010s anyone building a mid to high end gaming PC was using a quad core CPU, and with 4+ cores it's really hard to care if onboard sound is using a few percent extra CPU.
And while 3d audio is/was a cool concept, most people don't really have a sound system that will really take advantage of it. Even most "serious gamers" that I know use headphones or stereo speakers... now that I think about it I'm pretty sure I'm the only person in my friend group with a 5.1 speaker setup on my PC.
And while 3d audio is/was a cool concept, most people don't really have a sound system that will really take advantage of it. Even most "serious gamers" that I know use headphones or stereo speakers... now that I think about it I'm pretty sure I'm the only person in my friend group with a 5.1 speaker setup on my PC.