There's some basic algo-comp in Logic and Ableton already. But generally, musicians really hate the idea of having a machine writing all of their music for them.
This even applies to musicians who only work with loops, and to DJs who only work with complete tracks.
I think there are business models for algo-comp, but this isn't the best one. I'm not sure JukeDeck is necessarily heading for the deadpool, but it's maybe 50:50 at best.
Also, the production values on good stock music are very high - higher than here. Try https://www.shockwave-sound.com/ for some examples.
I think JukeDeck isn't quite up to the lowest quality tracks on there, and it's a very long way short of the better tracks.