It is generally understood that having a strong password is much more secure than a single sig. An attacker would need to have both the seed & passphrase which might be held in different jurisdictions.
My question is if instead the attack is one of using computing power to brute force in binary. Its guessing 1's and 0's and both the single sig wallet and the single Sig plus passphrase wallet have an equal number of ones and zeros, isn't brute forcing essentially the same?