[cocktailpeanuts]

I think you can throw out support for these legacy technologies IF:

1. Doing so results in competitive advantage--such as being able to move significantly faster, being able to maintain significantly cleaner codebase, etc.

2. Your library does something unique that no one else does - If there are tons of other libraries that do the same thing, you will be thrown into a feature war. I guess that's fine and there's nothing wrong with that but I personally wouldn't want to be in that position.