• In the past the way build-tools were used for code generation (in many language SDKs) assumed a strict separation between resource attributes and semantic attributes
• This assumption is not true anymore, as there are attributes that can be used as both, resource and semantic attributes
• Currently, there's no (easy/at all?) way to use the build-tools for code generation in a way that the above separation applies if we have namespaces in the registry that would contain both, resource and semantic attributes
• With the migration to a registry-based attributes model, the current limitation

The above leads to the fact that some work on semantic conventions is blocked, because we cannot introduce namespaces with a mix of resource and semantic attributes.