High-level documentation about "lossiness" of 3.0 to 2.0 downcasting

[nickwalkmsft]

I help maintain a tool that does some processing on version 2.0 OpenAPI specifications. It offers a basic level of support for version 3.0 specs by using OpenAPI.NET's ability to read in v3.0 specs and serialize them out to version 2.0.

We mention in our documentation that there's some "lossiness" involved with this conversion, but I'd like to provide a little more detail - not fine-grained, but just a basic overview of what to expect. Is there any OpenAPI.NET documentation that covers this at a high level that I can point to?

Thanks!