For personal accounts though, I somehow feel uneasy about reliance on a small piece(s) of HW.
Most people already have a small piece of hardware called a phone that can be applied to the same effect.
Free/open source TOTP apps are readily available for both iOS and Android. This isn't rocket science, it's a simple SHA hash that either works or it doesn't.
What if you lose your phone? Remember --- this is 2FA so you need more than my phone to access my accounts. My TOTP app is password protected and I have a backup of the keys so I can easily transfer to another phone or use a desktop app to access my accounts.
What happens if you lose your hardware key? Perfect security does not exist.