Disagree pretty strongly here. Gab being hacked is bad, and a bad look too, but social media getting hacked is something that does happen. Literally every social media platform has had hacks at some point, including the mainstream ones like Twitter, Facebook, etc. Jack Dorsey's twitter has been compromised before, so Torba's Gab being compromised too is not something beyond the pale. Couple that with the fact that any Alt-Social Media is necessarily going to be a disproportionate target for it's size and be drawing on less in terms of talent than legitimately big Social Media like Facebook/Twitter does, the fact that it is going to get hacked sometimes is a tradeoff we have to make.
The obvious solution is not to put information that can be used to doxx you up, which Gab is very good about not requiring. The only thing that could be that they require is an email address, and at least from the article you linked and Gab's own comments those weren't even hacked, or if someone put their real ID in a private message, which isn't advisable anywhere. Passwords is an issue, for non-doxxing reasons, but again, that's something that does happen fairly frequently, and without an ID to link that password to it's not like they can be used for much.
Absent you having put your full name and address in a private post for unclear reasons, the media knowing your various internet pseudonyms private posts might fuel a buzzfeed article or two but is hardly "life destroying." At worst you can just change your existing passwords or grab a new throwaway email and make a new account.
Parler's hack was uniquely bad in that Parler had some sort of "verified citizen" status, which you could get by uploading pictures of your driver's license. This meant that a hack of Parler was inherently exposing their users to a lot more risk, a risk that Parler implicitly (or even explicitly, I'm not sure) encouraged their users to take.
And yeah, people putting themselves on the front lines of the culture war, using their real names and putting significant financial stakes into that fight, are going to be a bit odd. Trump's a bit odd too, and it's not like his twitter replies were a hugbox either. I'm not to keen on smearing guys putting it on the line to try to give right-wingers a place to meet and organize though, especially over pretty thin issues.
Tbh, if you hate alt-tech / alt-social media... why are you here at all?