I understand what you are trying to do, but consider a few things:

• Perhaps your way isn't always the only right way when it comes to safety?

Sure, for some things it's pretty clear-cut, but there are some situations where there is more than one way to safely do something depending on different situations. I might get pretty defensive if someone told me to wear a helmet because I feel they are ineffective in most cases - it can be a real gray area, with no clear "right" answers. Just saying that maybe in some cases, people get mad because they really don't think they're doing anything wrong and are doing what they believe is safest - and maybe sometimes they're right?

• Perhaps you're going about it the wrong way?

I tend to think addressing problems as you see them on the street will get you absolutely nowhere. People are defensive about their driving, I don't expect riding is much different. Confrontation simply makes them dig in their heels and get stubborn.

Consider attempting your advocacy in a way that might be more useful. Some suggestions might be: Volunteer to help with safety classes (or organize classes), put up flyers for LAB courses already running, talk to the city about ways to get involved, etc. LAB may be a helpful source for you if you are interested in this, and there are plenty of experienced advocates here as well who are great sources of information on how to go about this.

More "passive" confontation like this I think is more likely to get people to think than on-street confrontation, which is likely to just result in defensiveness. There's more than one way to skin a cat, and I think you may be doing it in a way that's not as effective as you could be.

At any rate, best of luck.