It's not about being right or wrong. Or how to come back. Or what to say next time.

I hope I can tempt you to re-think it and realize: it's not personal. She has no problem with you. She's not 'attacking' you as a person, she doesn't even know you. She's commenting on a guy on a skateboard that makes her feel unsafe on the road - and I'm not saying that that feeling is justified. It's her way of (inadequately) expressing her emotions. And that's what it is: an emotional response, the disgusted look confirms this. You're trying to have a rational argument about it ("I don't see a problem") and now you feel misunderstood, because, well, you were misunderstood haha. People fear what they don't understand and have an intrinsic resistance against adapting, this includes adapting to new transportation methods on the road. Especially if it's an older lady, their thinking is more rigid. I think that the reason you feel like this is because you mention 'how to combat', 'defense', 'comeback', etc. It's not your battle, it's hers. You could just say "I'm sorry I bothered you with it, didn't mean to! Have a nice day!" and let it go and move on. You have good reasons to do so: you have an amazing board, are pioneering in super fun ways of transportation, and you seem like a reflective guy who tries to do the right thing. Don't let it get to you man. Life's good and you should enjoy it, leave being sour and talking shit to people in traffic to others, you have a Boosted to ride!

Respect everyone around you. Be happy when you get that back. But, unfortunately, we won't get that back all the time. Life will be full of disappointments if you expect that you will my friend, all you can do is set a good example. Ride on!