Bias warning --- I'm part of the group doing this work. For an end-user, your arguments are fine. A single developer or team can indeed use whatever tool they want and adapt their code without too much difficulty.

The real challenge comes, however, as you try to build an ecosystem of libraries on top of multiple different APIs. You end up reinventing the wheel or struggling to maintain multiple versions of the same library.

Some cooperation is immensely helpful at the lowest level, and we hope ultimately to be helpful to the different tool builders in providing information and guidance about what is already a standard and agreed upon in the space.

This is not about establishing or forcing behavior. It is about documenting and clarifying best practices that have already emerged as well as potentially giving libraries a way to signal to downstream developers of additional libraries that they adhere to the standard.