This is unfortunate--in a just world everyone doing this would be imprisoned for many years and have all their ill-gotten gains stripped from them--but a real fact. And the typical NSA software developer is certainly highly qualified and very, very smart. Going purely by business concerns, if you have a need for someone with the skill set that'd come from working for the NSA, you can't afford to pass them up just because they worked with the NSA.
You can also be sure that, even if the NSA were disbanded fully and all its employees hated so much that they could not get domestic employment anywhere, many international actors would be extremely excited to pay top dollar for their talent. And by top dollar, we're not talking piddling six figure salaries.