a better response
I can't help feeling that in addition to name calling (though justified it seems), would have been
a) a challenge; don't call to ban something you can't do, so get yourself a full bike licence and complete at least 2,000 miles on a big bike before passing your judgements. After all, most bikers can also drive cars, so we know what we're talking about, you don't.
b) a list of statistics, with references putting bikes into perspective against other activities including driving, cycling, and a variety of sports. For example I recall hearing (From Kevin Ashe I think) that drviers who also ride are 10% less likely to crash or somesuch. Figures regarding a bikers vs a drivers chance of CAUSING an accident would also be favourite, as I suspect, but don't know for sure, that it would be in our favour. I read recently about that French traffic survey, 45x less dangerous than cycling it seems.
this way we're more likely to show that we're not as bad as he says, and should be encouraged not banned. You never know, we might even convert him, and that would be a feather in our cap!