Hacked emails is certainly a cybersec thing, but the fact that backstage politics secrets sometimes become public is nothing new, and not necessary bad for democracy.
When a totalitarian adversary does it to aid their preferred candidate it's absolutely terrible for democracy.
Sorry, I hear "when it's against my preferred candidate it's absolutely horrible". Transparency, and informed decisions are usually claimed to be good for democracy. Hacked emails may play for this, even if done for another reason. Democratic elections are always go with dirt-digging, and spills, and it is essential part of the process even if someone doesn't like it.
In most cases dirt digging isn't usually a serious problem.
When a totalitarian adversary does it to aid their preferred candidate it is.