Have no auditors who can prove all this virtual Bitcoin trading on exchanger backed by moneyfull private keys.
When people start to windraw Bitcoins from exchangers MTGOX2 will happen.So better keep your Bitcoins outside echangers for safety.
https://electrum.org/ if you can not use bitcoin core wallet.
If all crypto users withdraw all coins from exchanges what would happen with cryptocurrency, what would be the value of coins in your Electrum wallet? Trading is one of the key factors in this industry, it have big risks because of constant hacking threats of exchanges, but with today's fees it is very easy to move coins in or out from exchange.
Your statement that some new Mt.Gox will happen when people start withdraw from exchanges is complete nonsense, do you even know that Mt.Gox is hacked and it is not destroyed by users who withdraw their coins?
I know what you want to say in your post - it is not smart&safe to keep coins online and this is true//but the way you wrote it, looks pretty bad written.