If it's enough of a problem to get a countermeasure implemented into the server, I doubt it'll come back, not with how many people complained in the past.

What if it was a perk that gave you the ability to shoot while in air but decreased speed or health

it's removed for a reason, and a rather significant reason
literally just cope, jump crouching & shooting probably won't come back soon because of gmod's bassboosted hitbox sync