Most people don't know about Delta-9 yet. It was brought to my attention when I saw a video about a business selling Delta-9 drinks in an illegal state.
Delta 9 is the long-known active ingredient in regular marijuana. You're thinking of delta 8, which is a new isolate.
This is kind of my point though. When I talk about this stuff, people assume I just mean delta 8, or CBD or whatever. Nope. Straight up delta 9 edibles are 100% federally legal now.
You could explain why it matters, instead of complaining that people don't understand. Delta-8 is also psychoactive and not well known so it's easy to mix up.
CBD has been legal for a while and is completely different than THC products so it shouldn't be compared.
Stating Delta-9 is legal, not Delta-8, is not that big of a difference. If you think it is, you should talk about why it matters because your attitude obviously hasn't worked thus far for dealing with people who just don't understand. Maybe, you're not concerned with people understanding as much as you state.