By this argument every major tech company should have been hacked by now but somehow they are doing just fine. Just because the person running Mt.Gox was a rube doesn't mean being hacked is inevitable.
It might not be technically inevitable, but it's a great way to look at things security wise. Especially when explaining to newbies.
I have kept hundreds of bitcoins on addresses with unencrypted private keys stored in email/txt files on the cloud for years and the only times I've had bitcoin stolen was when I handed it right over.
Not because it hasn't happened to you it doesn't mean it wouldn't happen to a lot of people. People getting their funds stolen through storing their keys anywhere unencrypted isn't anything new now.
Gox is exactly why any exchange worth its salt needs to be audited.
Exchanges, especially the bigger one such as Binance, are surely getting audited. It's just that being audited even by the best firms doesn't ensure 100% security.