Every non-Microsoft browser vendor used to cry themselves to sleep at night from days fighting against vendor lock-ins and corruption of standards. They certainly care if it all goes south.
I suppose people don't want easier browsers because they imagine they are easy enough and can't imagine something better. At least I hope that's the reason, and not that they fear change, or are indifferent to the needs of people other than themselves and prefer to design for that alone.
There's no way in hell I'm crazy enough to make a browser, though. I'd rather run for elected office, or eat an entire Volkswagen Golf.