$150 today is not the same like $150 few years ago, and most hardware wallets are starting around $100 price target and up.
You're right, but it doesn't seem that they even tried to mitigate that problem by choosing alternative suppliers, and by continuing on that route, $300 hardware wallets would become the norm in a year or two.
There is no a single word about code on their website, and that usually means it's not open source.
In the latter part of "
this blog post", there's a PDF link with some information about an issue surrounding certain parts of the code:
Bitkey server code that implements the co-signing policy is not yet verifiable
○ We will open-source the code prior to general availability - but this code runs in an Amazon Web Services environment managed by Block whose properties customers cannot directly verify.
While we may be able to provide verifiability through AWS’ Nitro Enclave Attestation, we have not yet evaluated this approach nor implemented it