I am into programming, like you are. I also would rather benefit from the thousands and thousands of developer hours that have gone into the react core, and not have to train every new team member on a crufty ten year old bespoke codebase. I do try to keep my external dependencies low, but core utilities are not worth rewriting from scratch.

sadly we aren't all as smart and worthy as you are, and don't have a decade old react-like hanging around. some of us even prefer the idea of using an open source library for the various benefits of doing so.

If you'd shared that system 10 years ago maybe we'd all be using that instead of React!

Where I work, we use React because it's easier to find new hires (because they want to work with React) and quicker to get them up to speed on a project (because they already know the framework).

It's also easier to integrate and extend any 3rd party components, as we're already familiar with the boilerplate.