passphrase of at least 10 - 12 characters, this is quite enough to protect the compromised seed
It is far from ideal, though. A 24 word seed phrase provides 256 bits of security. 10 random lowercase characters provides only 47 bits. You shouldn't be relying on only a passphrase for all your security, and definitely not one so short.When you iterate over a seed of 24 words (256 bit), you have the opportunity to find millions of other wallets, since most wallets use the bip39 standard, in this case there should be sufficient redundancy. When you iterate over the passphrase, you have the opportunity to find only one single wallet, so such protection (10 -12 characters) will be enough. Read again the article https://blog.trezor.io/is-your-passphrase-strong-enough-d687f44c63af?gi=a11722e479d8 there is a table with examples of password phrases and the approximate cost of attacks
