The reason is not “solved” is that everyone has a different “problem” so it’s impossible to solve for all of them. Businesses solve for their use case using the the solution that fits their constraints.
Having a multitude of “solutions” is a feature, not a bug.
It’s not like a handful of form controls looking like Windows 95 and hyper-specific React form fields are the only options. Here’s an entire industry creating millions of components for basic fields; surely we can come up with better extensions and configuration, slots and styling opportunities that make life better for everyone.
Having a multitude of “solutions” is a feature, not a bug.