Not everything supports Yubikey/FIDO U2F at this point, so that wouldn't work for everything, although I do have one. My Gmail account itself is behind a Yubikey (and a a backup Yubikey), not a 2FA app, because I'm trying to avoid a Game Over scenario. The Gmail address is the recovery address for my password manager account, so getting that pwned is basically the keys to the kingdom for every other account.