I think you’re mixing two subjects here: he seems to be saying that it doesn’t work any differently, which I’m sure is true – all they do is follow someone around, fight things, and occasionally res someone or each other, all of which can be found in other NPC’s – but the skills they have do make a very noticeable difference to their effectiveness in gameplay.
If you watch some generic NPC in the world get into a fight with something, often they just stand there staring each other in the face, using an attack every few seconds, and occasionally something from a small pool of abilities. Often very useless ones. Ever seen Iron Legion Engineers drop a net turret, stand in place anyway, drop a medkit they aren’t even aware of to walk into, and throw a wimpy little grenade now and again? Yet, they’d be so much less pathetic if they’d do something as simple as dropping a healing turret instead.
So many of the things in the world (allied and enemy alike) feel a breeze start to blow and cough up some meaningless utility then fall on their faces and die. Granted with some enemies it doesn’t matter as they’re so generic they could just make more of them to give us something to do instead, but it seems kind of silly when you’ve got some town/camp/base sending out patrols which just walk a few feet, fight, die. If you res them they just get into another fight and lose that, too. And if they encounter anything not in their (usually) two person group, even another of said groups, they won’t revive it regardless of friendly status.
Having some that are actually useful, even if far from being able to do all this themselves, is so much better after dealing with a world full of things not even worth the time it takes to revive them.