I don't agree at all. It's on my keychain, next to my keys, a nice symmetry. When I need to login I hold it to the back of my phone for half a second. It's incredibly easy and would be even easier if it weren't for the UX presented by iOS, Android, and Windows where they try to be the provider. Android has gotten a bit better. Windows is the worst about it afaict.
I don't like having to fetch my keys when I'm at home at all, which is where I do most of my authentications. I'd have to get up, walk to where I usually keep them, walk to my computer with them to authenticate, and then either walk back or forget the keys somewhere in the house and have to search for them when leaving (or detach the authenticator from the keychain and then not have it on me when I'm leaving).
That's why I don't like using USB authenticators on a regular basis.
It’s recommended to have at least two anyway, to still have access to your accounts in case one is lost. That means you can keep one key at your desktop and you’d only need to go up to get your keys when adding them to an account.
Having two in the same house is a pretty bad compromise. Ideally you'll want one of them to be physically somewhat distant (in case of a fire etc.), which makes things even less ergonomic.
