Disclaimer: this question has a theoretical importance for me, try to better educate myself about the cryptographic principles and the signature schemes. I do not mean to imply that, in practice, schnorr signatures are less secure than the current 2-2 multisig transactions / scripts.
I am currently reading the document of musig and about scripts without a script. In my opinion, an important common idea in both cases seems to be able to have a single signature produced from several private keys.
Suppose I can force the private key of a public key within a reasonable time, say 1 month (for example, because I have a fairly efficient algorithm for the discrete register in ecdsa (which I do not have). I also suppose I can invert the hash function of the Bitcoin addresses quickly, or suppose that we only know the public keys because I am the third party in a security deposit service)
Would not be able to break a MuSig address within 1 month (under the previous assumption) by splitting the added private key into the added public key, while in the configuration of a common 2-2 multisig wallet it would take 2 months for to be able to provide two valid signatures since I would have to apply bruteforce both private keys independently?