Jones was never signed or conceived to be a regular starter - what else is new! Rather, he was always viewed as an 'impact sub' to be brought of the bench.
What has Jones done since returning from injury? - not much actually. But its hard to do much if you aren't given playing time - which is exactly my point!
All great managers are never afraid to drop - even their best players - if they are found to have violated team rules or acted in a way that hurts the team. It's something, for eg., Fergie was never shy of doing.
But if, as you imply, Morelos should be exempt from these rules because he '..is our best striker...', whilst others such as Jones end up being benched - because of one rash action - then you are accepting a clear double standard.
If this is indeed the case its lousy man-management on Gerrard's part.