Why would more confirmations help in a 51% attack scenario? After the 51% attack on Bitcoin Gold. The developers of the cryptocurrency recommended the exchanges to increase the confirmations. I don't understand why increasing the confirmations would help if the attacker has control over the history of the blockchain. I'm missing something for sure.
If the exchange waits for 6 confirmations (1 hour) and sends the dollars then, it could be possible that no one even noticed that there was such an attack. Then a scammer could pay out twice.

But if the exchange waits 12 hours for example, some miners will probably recongnize that they do mine on a shorter chain within this time.

In the bitcoin system, 6 confirmations mean in more than 99.9% of the cases that the transaction is done. There are only a few scenarios in the bitcoin history when that was not the case.

But you need less mining power to attack Bitcoin Gold. So I would aggree that the exchanges should wait longer.