I haven't played in a while, so keep in mind that I haven't seen the latest changes, but I think I would miss it. Sombra has always been squishy and a bit underpowered in damage output, so getting value out of her meant using the rest of her kit to make up for it. I enjoy that kind of challenge more than endlessly twitch-aiming and clicking heads.
Stealth in particular has a funny and I think mostly undeserved reputation. On the one hand, it doesn't feel good (as another hero) to have positioned yourself well and have great aim but still get assassinated by an enemy who appeared behind you out of nowhere. On the other hand, Sombra doesn't just appear out of nowhere. She is visible when she's near you, and her footsteps make noise, and she can't attack until she fully de-cloaks and sits through a cooldown, and she announces herself when she de-cloaks, and she's vulnerable during the cooldown, and she's often alone the whole time.
All these weaknesses combined leave ample room to shoo her away (or even kill her) if you keep aware of your surroundings, rendering all her set-up time wasted and forcing her to go heal up. But having tunnel vision can be a death sentence when Sombra is in play. I think this is why I'm seldom killed by Sombra when I play another hero, yet get plenty of kills as Sombra when my opponents aren't paying attention.
If stealth were gone, I expect her mobility would still be appealing, but I would really miss the high risk/reward of relying on stealth and game sense more than teammates for protection, and I would really miss the challenge of reading enemy intentions and awareness levels to find kill opportunities. Endless point-and-click is pretty boring to me.
Also, everyone needs a counter. Even Widowmaker.