I think hashtags in theory are fine, but either they sometimes focus to much on being gimmicky or are kind of abstract and vague. Kinda like how people don't care about vague descriptions of Aristotelian physics.
Scandal-gate, it's pretty annoying on the other hand. Now I of course wasn't alive when Watergate was first a thing, and I am assuming the first few times people used it it made sense and was amusing, but now we just applying -gate to not just every scandal but anything that is remotely controversial. Gamergate, emailgate, modgate, Obamagate, CFCgate, chickengate, Xwedodahgate... well, guess I can't do much about it.