We're running in circles, but since you mentioned it again:

They use MetaMask, so they need to save their seed phrase offline, encrypted? Why do they need that? Someone breaking into their house can also just steal the PC, where the seed is stored, unencrypted, in MetaMask, no?
You mentioned that a text file is not secure. Sure; a virus can access this file. A virus can also access MetaMask's wallet file; right? Where is the benefit of storing an online seed on an encrypted offline device?

Again, in my opinion, encrypted, offline backups only make sense if your main wallet is offline, too. But since offline wallets can't usually connect to the cryptoplatz vault, there's no way of transferring the seed except through an online device, which destroys the whole purpose of it all.