I think this is still valid. More and more Nitrokey devices will get certified.
A Relying Party can choose the attestation and conformance level of the device.
The FIDO2 standard allows self-attestation.
However:
Some services though, such as those in the financial industry or the public sector, may be required to know more about the devices that are accessing their services. They must guarantee that encryption keys are secure, biometrics are of a certain level of accuracy, etc. This is where the second aspect of attestation comes in, which is enabling the service to trust that the registration request is coming from a specific model of FIDO authenticator.
FIDO TechNotes: The Truth about Attestation - FIDO Alliance
Whether it’s a smart move to require specific attestation levels for FIDO2 devices is debatable. It definitely is an entry barrier for open source implementations.