While I'm not well informed enough to have a strong opinion on the matter, the bad things I've heard are mostly related to his profits from currency speculation and similar, which many people feel were immoral actions taken by Mr. Soros and untimately harmful to the nations who's currency he profited off by shorting. That's plenty of information regarding his past financial dealings if you are interested.
Those were essentially the UK's fault, and it's not like Soros was the only one taking advantage; if you're a market economy it's hard to blame a market for acting like a market. Today, it'd have been automated trading systems, probably.
Edit: I do think, by the way, that it’s telling that Soros is about the only example people ever give in cases of market forces harming a country. When Britain sold gold just before the gold bubble really inflated, no one blamed the gold traders; they blamed Brown, say.
That might well be true, but I have to assume there are plenty of wealthy financiers out in the world making money from currency speculation, and you and I have never heard of them. It's hard for me to believe 'shady currency speculation' is really the root of the antipathy toward Soros.
It's like those climate change deniers who have a ready list of negative stories about Al Gore: I'm sure Gore has done some obnoxious things in his life, but you get the impression they went digging for dirt to justify their pre-existing distaste for the man.
He brought down Bretton-Woods in the 70s. That system was simply ripe for the taking, had almost collapsed in 68 (because the German Mark being fixed to the Franc and Dollar just doesn’t work when growth diverges), and would have collapsed eventually, possibly with more damaging results.
The criticism of Soros in Eastern Europe is simply the fear of the local wannabe strongmen of opposition. Soros funds mostly journalism and other civil society institutions (debate clubs at universities etc).
That criticism is channeled through anti-semitism, which still has currency in Hungary. Do a google image search if you don’t believe me.
In the US, he’s just a welcome foil for the alt-right to counter the Koch narrative, even though Soros historically did not actually support candidates, only causes. The anti-semitism is more subdued there, because it’s not (yet) acceptable in polite company. But polite company is almost as bankrupt as a Trump casino now, so we’ll see.
