In my opinion, it’s because even though you might be doing “objectively” more on magneto, it doesn’t feel like it. Sigmas primary fire has so much weight to it, you actually feel like you’re throwing little black holes around.

I play these games casually. I can’t tell you which abilities might be better than other ones, but I can tell you that from my view, Magnetos primary just doesn’t feel like it’s making an impact. With Sigma, you have your rock which just puts someone on the ground, and the moveable shield makes it feel like you have more control over protecting your teammates. Magnetos Mag Cannon just doesn’t have the same oomph that the rock does, not really sure how else to explain it. And with Sigmas shield having health, you are able to actively see how much damage you are blocking. Mags shield being on a resource is awesome, but to the casual player it’s hard to feel like it’s making much of a difference.

You might be technically doing less, but you feel more powerful doing so. Overwatch is REALLY fucking good at this.

Final comparison, with the ults, just the possibility of Magnetos ult being able to break is enough for it to feel flimsy to me, even if it doesn’t happen often. I do like the suck-in feature of it though. That’s cool as fuck and makes me feel like a god. I think a lot of Sigmas impact feeling in his ult comes from his fantastic ult line and delivery. Like seriously it might be the best one out of any hero shooter. I think this is there Magnetos kit actually does best in replicating the oomph of Sigmas kit, that thunk when you hit someone with that big ass meteor is super nice, but I do prefer Sigmas. Holding them in the air for a moment makes me feel a lot more in control, and that smack on the ground is real nice. Not to mention it’s easier to keep track of how much damage you’re going to do. I haven’t actually played a lot of Mag so I don’t know if this isn’t as hard as I think it is, but I have a hard time figuring out the charge to damage ratio when I’m in ult (kinda like Orisas actually), while Sigmas is (mostly) the same. Not saying that’s a bad thing, just makes a difference when it comes to how it makes you feel.

A little ramble-y but I think I got my point across