Well I'd disagree about the 200mm point (and even if it were true its still going to be perception that drives sales) but I think your talking more than just super tele's, even something like the 24-105 would be unbalanced on an M9 sized body for me.
This is another point that the peanut gallery is generally missing.
A small, lightweight camera is pointless without small, lightweight lenses.
And there are some very hard physical restrictions that come into play when designing lenses. The Shorty McForty is about as small and lightweight as a lens that covers the full 135 format image circle is going to get, and just look at all the people bitching because it's only f/2.8. If you want faster-than-f/2 in a normal prime, you're not going to get much smaller and lighter than the Plastic Fantastic. And if you want something that fast and either wider or longer, it's going to get really big and heavy right quick.
So, if you want small and light, you'll either have to go with something slower or that doesn't have as large an image circle. And probably both.
Surprise! That's exactly what I've been describing: something that bridges the upper end of the P&S range and the Rebels.