Any device or software that you use to create, store and/or secure your keys has full access to your keys.
Anyone's best bet against falling victim is to use open hardware and open software that can be audited and signed.
This would mean even the Coinkite hardware is untrustable.
I have my keys memorised
I hope they were randomly generated, ideally by a good source of entropy like dice. A computer uses pseudo randomness and is probably good, but not all randoms are equal and any attempt to pick or reorganise your words to memorise it better will only reduce its security.
To be clear, I am speaking truth, but sometimes there is "secure enough". If you strive to only ever use the best security you can find, you would become paralised and would never secure what you needed to secure.
If you apply security beyond your own understanding, there is a good chance you could compromise the security or end up in a situation where you can't figure out how to get access to your protected thing because it is too secure for you.
Don't let perfect be the enemy of good.
You grossly overestimate my knowledge amd skills 🥲 No, they weren't randomly generated..its the keys I got when I bought my ledger. I'm ngmi, am I? ðŸ˜
