To add to this: Supporting old stuff costs time. If the company (or a group of companies) believes they know better, they can contribute the code to change th

To add to this: Supporting old stuff costs time. If the company (or a group of companies) believes they know better, they can contribute the code to change this. And maintain it. Or pay someone else to. It's perfectly viable and it accurately reflects the cost of the business's decision to not change something. Otherwise no, most browsers must be safe for the lowest common denominator, and they do know better than most.