Because its been over a decade now, and somehow, they're still behind? If I'm honest though, to me it feels like a Kodak situation - the legacy companies could do it, but they like their existing product lines - the ones that bring in revenue today, that they know how to build, that only need small design adjustments each year, that work with their current structure of suppliers and dealers. Why worry about this new-fangled thing you'd have to spend a bunch of time and money to get right when its only going to be X% of your sales for years?

On the other hand, Tesla (and the other new electric companies) have nothing else. It's electric or die. It's carve a space out in the market now, while the legacy players are still dragging their feet, still figuring out battery issues or production issues Tesla dealt with 5-10 years ago, still figuring out how to make good software for the last 20 years, still trudging along as if things haven't much changed. Kodak didn't lose because digital cameras were harder, they lost because they didn't want to cannibalize their existing products with something easier and cheaper.