They can also make them without React and React is one of the heaviest of current generation of client side front end tools, by itself. Without a router. Without an additional state library like Redux. Un-code-split-able. So what's extra good about React for users that justifies "taxing" users with React?
Kinda playing devil's advocate here, since I do think there are use cases that React is the best choice for. I just also think it's used way too much when it's not.
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