You should always encrypt your wallet, and never download anything you don't trust 100% to a computer where you store coins.
That said, this hack had nothing to do with SDC. If the wallets were properly encrypted, the coin's couldn't have been stolen.
2FA works well for accessing secure online accounts, but it doesn't make much sense for a wallet that is in your control. I personally wouldn't want a 3rd party involved in securing my funds. It essentially takes the decentralization out of it. Like storing your money in a bank. If you want maximum security, you can always store your coins offline.
Absolutely! The biggest personal theft I'm aware of involved a fake wallet downloaded from a corrupted link.
Machines are cheap, most of us probably own several coins so you can dedicate a machine to all of them, get rid of the browsers and e-mail, lock it down, back it up, etc. Even if someone steals the machine, as long as you are backed up and encrypted you can be up and running with the coins moved to new addresses before they figure out how to turn the damned thing on. Don't let the bastards win!