No, you're good. Necropotence will still perform exactly as it did.

The crying is because hardened ward and annulment are now capped to a percentage of your max health. This means it's no longer possible to put an obscenely massive damage shield on your sorc, and just shrug off incoming damage. Particularly in PvP.

The set still works. I cleared Maelstrom with a Necropotence/Lich build earlier today. There's nothing wrong with it.

In endgame content, you're no longer able to cheese placement mechanics with annulment and ward. That's it. If you really want a massive shield to break a one shot, you can still achieve that with Barrier. I do recommend that skill, it's very useful situationally.

The MagSorc's still kicking, it just had a more broken toy neutered. Don't let people get you down because they're salty.

I can only speak from my own perspective. I have a dear magsorc who runs with only a matriarch pet. She wears Necro + Julianos. She is a PvE solo build who has always focused on sustain and survival over dps. She was neither a glass cannon nor overpowered. I have been testing her today after her empowered ward nerf and the elegant joy I derived from playing her is not there anymore. I have decided to retire her. For those pet sorcs who fit into the mold that the developers are pushing, I'm sure they can adapt and adjust. I simply have definite ideas of how I want to play a magic sorc and the class no longer supports my objectives.

I would not recommend a magic sorc without a pet though, as the class loses much passive performance without a pet. If you want to play a mage without a pet, I'd recommend a nightblade or templar in that order.