Should I transfer all accounts to Aegis or spread them across 2 or 3 similar apps?
Just one that’s separate from your password manager is enough. You just need to make sure that they aren’t stored in the same place as your passwords, otherwise it nullifies the whole point of 2FA.
It doesn’t nullify the whole point, it still protects against credential stuffing attacks for instance. I tend to use Aegis for high-value accounts and Bitwarden’s built-in 2FA for low-value accounts since the convenience overrides the extra security of an external 2FA for me.
True, I just use my PM for 2FA as well for the convenience.
If you are managing 2FA within your Password Manager itself. Then, Secure the vault using 2FA.