Why I'm Disabling Crossplay (and why you should too)
Aim-assist.
Even the most subpar controller player stands a fairly good chance of dealing quite a lot of damage if they're engaged at any distance other than long range. Having a 3rd party system making 0ms micro-adjustments to perfectly track their target will do that... and console players have an even stronger version of aim assist.
Yes, I've playtested both M/KB and controller extensively; as well as played on console extensively, so I know exactly what I'm talking about. The difference between aiming with a mouse v. aiming with a controller (except at long range) is immense. The behaviors exhibited by aim-assist at close to medium range are no different than the behaviors I expect out of a soft aim-lock; because aim-assist is, in essence, a soft aim-lock. The only thing that keeps me from switching back to controller to abuse the built in aimbot that Respawn provides is that it hurts my performance in other games helmed by more serious-minded developers that aren't concerned with pandering to as many players as possible.
As far as the argument "ohh, weeeeell, controller players have disadvantages elsewhere 😢 " that's their problem. It shouldn't be everyone else's problem. If they wanted handicaps then they should go join a bowling league. At least then their handicaps would be reflective of their skill instead of their chosen method of input.
In fact, if controllers having a disadvantage in other mechanics is a valid reason then the simplest solution would be to put controller players into controller lobbies. Let them all have the same advantages and disadvantages as well as compete amongst themselves instead of being obnoxious additions amongst players actually testing their skills.
Will respawn ever do it? Highly unlikely; but if they had any concern for the integrity of the game then they would.