It's not a case of the wheel needing to be round enough. The wheel is old and has not been able to keep pace. We have many people walking aside the wagon repairing the wheel at every turn. Those people are the current browsers. The wagon is the current technology and the people going along for the ride can see just how painful this is.

Anyone who has attempted to implement trivial things, like thematic scrollbars or cross-browser capable code, or dealt with dom thrashing via JavaScript, knows the amount of effort going in (or knowledge required) to do trivial things is ridiculous; considering how long we've been travelling down this road. Why are we still using a wagon? And why do we want to build more of them running in parallel?