So what ways of keeping bitcoins safe do you recommend then? Many people consider hardware wallets as something that is not possible to breach because they were told so. In both Ledger and TREZOR there were discovered vulnerabilities which allowed potential attacker to extract the seed. I haven't heard of any issues with KeepKey. I was thinking of using an air-gapped computer for storing large amount of BTC and a hardware wallet in case I needed to travel and have some bitcoin with me just in case. Have you ever used any hardware wallet?
Of course, the fact that we have to use closed source computers to run Bitcoin Core, makes it impossible to be 100% safe esp. against state actors.

I'm not objecting just confused: Is it about firmware, BIOS, fucking NVIDIA device drivers or what? We have Linux and Free BSD, don't we? Is it impossible to have Core's wallet running on top of a clean installed Linux?
I'm seriously interested in your term 'closed source computer', actually it is my main research topic for the last couple of years, I'm just wondering how deep is your interpretation of this concept and whether you have developed any idea as an alternative?