Why is gun run not a solos mode?

Well if all players are solo then that means that you can become a bigger target, next to that you really don't want to decrease the amount of players per lobby.

They probably designed it in such a way that when performing a bit worse than usual that you don't get completely destroyed.

Having some support on your team, it'll make it easier to navigate certain parts of the map, having some support isn't really that bad either.

I personally don't see an issue with the current implementation as it does not have a negative effect on my gameplay.

The only reasons I can think of to push this is "It's traditional" or "I just want solo's" which personally, both don't really make a compelling argument to change this.

I've also had some decently long matches here and there, wouldn't really want to extend that IMO.

Personally, think it's fine as it is.

They previously already explained why they aren't going to implement solo modes, not sure if it applies to LTM's too, though I think it could be applied to that area too.