Effectively it means all integrations must support multiple keys, and you’ll have to register both. Of course, this doesn’t work everywhere, such as AWS. In those cases, I typically use my “main” key.
I’d argue that the key breaking due to wear or being lost is less of a risk than human error: just last week I had to enter the admin GPG code for the first time in years, and I forgot it initially, which caused the device to lock itself, and apparently the recovery code didn’t work. Caused me a few hours of stress to get it resolved.
So yeah it requires some discipline. What’s important is that you need to identity the services you absolutely cannot lose access to: in my case it’s my email and password manager. For those two, I properly manage backup codes, regularly test both yubikeys, etc. The rest can all be recovered through email, if it needs to be.