Yeah, Andreas Antonopoulos explains why "security through obscurity" is a bad idea: most attacks are not targeted, but broad. Some examples:
  • If your seed phrase is easy to guess, someone will brute force it and they don't need to know who you are.
  • If you have corn in a hot wallet on a machine that's not secured properly, some malware or network exploits may steal it without targeting you specifically.
Avoiding being doxxed is prudent as a measure against targeted attacks, but not enough on its own.
BTW one of the benefits of multisig (over splitting the private key using Shamir secret sharing for example) is that it adds entropy.