Depends.
Single sig + passphrase is comparable to a 2-of-2 multi sig. You gain security by storing the seed backup separately from the passphrase backup, but you add risk because if you lose either one, you’re screwed.
A 2-of-3 multi sig, with each backup stored separately, provides the same level of security but builds in some redundancy to reduce risk of loss. But, it introduces the technical complexity of multi sig, increasing opportunity for user error.