If someone makes a claim of the 'ought' type, either they are talking about the world of is, or they are talking about the world of is not.

When people are talking about 'ought', they are frequently mean something that's different from 'is' but is like 'is' in that it's a primary concept. For them, 'ought' is not something that can be defined in terms of 'is'.

So IMO people who are talking about 'ought' often really are talking about the world of 'ought', and that's about all you can say about it.

If they are talking about the world of is not, then I quickly lose interest because the world of is not isn't my subject of interest.

You're entitled to be uninterested in the world of 'ought' as a primary concept as well. I am not interested in it either, so I can't defend the point of view of these 'ought' believers. I have repeatedly had conversations with them, so I am sure they exist.