Well doh... seed phrase is supposed to be secure in the first place. It's essentially the private key to all your private keys, or whatever addresses correspond to that seed.
Keep that stainless steel bolt and nut safe.
12-word seed phrases do seem secure unless (a) there are flaws in the implementation that reduce entropy such as the pseudorandom number generator, (b) attacker knows something about your phrase or (c) there is a quadratic improvement in computing power such as with quantum computers.
Interesting point, Bitcoin's private keys are 256-bit - was Satoshi just wasting space?
edit (again): So, Bitcoin's private keys have 128 bits of security when the public key is known, e.g. you're reusing an address, and 160 bits when they're unspent - https://bitcointalk.org/index.php?topic=1523431.msg15324846#msg15324846.Yeah, I do think that is all true.
Which is why, I don't necessarily update to the latest versions of anything unless it was announced as a major vulnerability or incident.
Most decent wallets that have been up and running for several months have good implementations, and as long as it's not the very first generated wallet on a computer that was not just turned on minutes ago ... meaning you let it run for a good while doing something else so the RNG can pick up stuff ... you should be good to go.
As well as the usual OPSEC and other good or best practices: offline, generate a few test wallets, try them, move around some coins, then create a brand new one for your cold storage and test it a few times that it generates the exact same address or can be recovered, and if using hardware wallets do the equivalent of a hardware reset or reformat or update the firmware after having bought it directly from the manufacturer opening a sealed package.
Corn and it's software are redundant and maybe overkill in terms of bitness. No one is quickly brute force cracking 90 bit pseudorandomly generated keys, let alone 128, 160 or 256 bits.
As mentioned in that thread, why spend decades cracking a key that may contain a few corns, when you can spend a few years mining and get more corns more consistently that way? (and if you're not mining with the latest hardware, just buy the corns today and lock them up for tomorrow.)