Yeah, the OpenSSL CLI sucks. So what's to be done?
Sure, we can build a 25519-specific tool with a less footgun-y interface. Fine, whatever, for that one use case.
Or we can build an alternative OpenSSL CLI that explodes OpenSSL and its numerous useful features in a general way and helps fix lots of use cases.
Nothing is to be done. Just don't use the OpenSSL CLI. It's a deeply cursed concept for a tool!