Well, not only the nation will be "punished" (and I don't think that punishing the UK for wanting to leave would be right).

This article is how the banks suffer, most of them are probably not from the UK. Not as a punishment, but as a direct consequence of Brexit.

And the EU will suffer too. So, Schadenfreude is maybe a bit short-sighted here...

Edited to emphasize that I do not think this discussion should be about punishment. And the linked article is definitely not about punishment.