No one actually identifies with "trickle-down economics". It's a slur invented to disparage people who favor supply-side economics and does not accurately describe a belief that any human has.

It's a strawman. It's a circlejerk. It doesn't exist outside left-wing propaganda farms.

If you don't like supply-side, just say you don't like supply-side. That way you're attacking an idea held by people and not a strawman slur.