This should be yet another reminder to never store coins online for long term, and always use strong 2FA on your account and your email.
That's right the recent event on QuadrigaCX and these one is compelling reason that not just to store coins for long term, but not put all your funds in a exchange because we don't know that there are bad actors like the one reported here. It's more of an inside job, but the good thing is that the criminal was caught.
to be fair most people don't "store" their funds on exchanges they have them there because they are trading and they have no other choice to have them on exchanges for example when opening up a (buy or sell) order and waiting for it to be filled. and that is when they get hacked and lose their money or the exchange scams them and they lose money!