Yes it does - pre-1992 cars, only have to pass a VERY basic emissions test.
Post-1992 cars have to pass a much more stringent test - and the it's almost impossible without a Cat.
Yep. But as above, you have VERY little chance of passing the Post-1992 test without a Cat ! (Although it can be done, occasionally)
Yes, that was his point about it being a 1990 car :)