Today the areas that were previous controlled by East Germany overwhelmingly vote for right wing parties though.

I believe the AfD political party in Germany won significant support in those areas of Germany that were once behind the Iron Curtain.

Yes, they won control of an entire state and almost won another.

People vote far right because they're fed up with the status quo, and perceive the far right can't be that much worse when everything is already so bad. Politicians who are not far right would do well to take this into account in their politics. Sadly, they don't, and history repeats.