The jerkiness is subjective - it's not an active problem to worry about or rely upon. So the market share of 2.3 isn't really a pressing issue.
G1 is a bad example - it is too weak spec wise. Aging hardware problem is not something anyone can do anything to resolve. With Google the pace of obsolescence is faster than Apple's but that's a fair price to pay and not many common apps are demanding enough to care about hardware specs. There is always going to be faster hardware and specialized software that exploits it - it's not a problem, just evolution that you got to manage.
Also now a days most Android phones do have decent enough hardware to not cause you the G1 class of headaches. So there isn't much to worry if you target 2.1+ phones which gives you 85% coverage.
The only solution for the developers of that uncommonly demanding app is to have minimum specs requirement for the app. And I have heard that Honeycomb will come with base minimum hardware requirements - but that may be a moot point as already most Android devices have decent hardware now a days.
My iPhone 2G on iOS 3.0 can scroll a list smoothly. Every brand new Android phone (possibly excluding the Nexus S -- I haven't yet used one) cannot. Sadly, since I still see devices stuck on 2.1, 2.0, or even 1.6, that fix will not come to everyone soon (or, for some devices, ever).
Subject to devices in use, firmware they are running etc. My Nexus One, Galaxy S with TouchWiz UI, or the Nexus S do not have jerky scrolling for instance. The G1 does. http://www.youtube.com/watch?v=9xEKrY0VQKQ
So it is possible today for people to buy Android devices and not notice any out of the ordinary jerkiness.
Sounds like what people said about buying American cars in the mid 80's. It was quite possible to buy a great, reliable American car. Unfortunately, other cars in the group pulled down the perception of those cars as a group, in sharp contrast to perceptions of Japanese car makes.
G1 is a bad example - it is too weak spec wise. Aging hardware problem is not something anyone can do anything to resolve. With Google the pace of obsolescence is faster than Apple's but that's a fair price to pay and not many common apps are demanding enough to care about hardware specs. There is always going to be faster hardware and specialized software that exploits it - it's not a problem, just evolution that you got to manage.
Also now a days most Android phones do have decent enough hardware to not cause you the G1 class of headaches. So there isn't much to worry if you target 2.1+ phones which gives you 85% coverage.
The only solution for the developers of that uncommonly demanding app is to have minimum specs requirement for the app. And I have heard that Honeycomb will come with base minimum hardware requirements - but that may be a moot point as already most Android devices have decent hardware now a days.