Why did this end with "USB"?
Discussion
If people try too hard to protect their home privacy, it's almost like saying they have something valuable to hide. It's the same when people use all those fancy cold wallets, it's almost like saying, hey, here is where I store my coins.
I guess the best way to hide or protect anything is to avoid causing any attention in the first place, so you use a simple USB to build your own cold wallet and keep your stash. 👀
It could have been SD card, it could have been airgapped laptop, it could have been writing your seed phrase on a piece of paper.
Because you know, the "fancy" tools are there to protect from automatic programs. Things that don't suspect, but just try to infect as many computers as they can and grab what they find.
Now I agree that buying a prebuild means you're in that companies customer list and if that list is leaked (such as it has been in Ledger and Trezors cases) than that puts you at a risk that could be avoided with DIY, but I have a vendetta with USBs!
https://www.howtogeek.com/203061/dont-panic-but-all-usb-devices-have-a-massive-security-problem/