Doesn't really matter, considering they aren't open source
Exactly.
Old smartphone can work better than Ngrave if you don't care about open source code, and you can also install Graphene OS of Pixel and get open source device.
You pay less money for this, and you can always switch back to use it as regular smartphone.
I think newer Pixel devices also have secure space, that is not exactly secure element, but it gives additional security.
Krux app can work on smartphones, but there are other wallets you can use without internet connection.
All that is good but seems to be fully off-topic (and pathetic at the same time)
It's not off-topic and it's not pathetic.
Seed phrase IS generated on Krux and Krux is DIY hardware wallet, not a banana.