I think OP is using “first class” as in “an explicit semantic affordance”, and you seem to be using “first class” as in “a supported operand” (or similar, feel

I think OP is using “first class” as in “an explicit semantic affordance”, and you seem to be using “first class” as in “a supported operand” (or similar, feel free to correct me if I’m misunderstanding). In which case both points are right, albeit orthogonal.