Keyonte has had stretches of looking like a starting level guard, offensively. Go look at his November/December splits where he was shooting about 54% efg%, on about 24% usg%.
Here is a list of guards with usg% above 20% sorted by efg% and you can see that Keyonte would be right there if he kept up that efficiency:
https://www.nba.com/stats/players/a..._PCT*G*20&PlayerPosition=G&dir=A&sort=EFG_PCT
He's also a good enough passer (27.4% ast%, 2/1 ast/to ratio) that he doesn't need to be branded as just a microwave scorer or can only come off the bench guy. He's a young guard who needs to be more consistent and needs to play defense. He's still got a tone of potential.
I would bet that this benching is a motivation thing, and not some indictment on where the Jazz see Keyonte's future being.