There are no interactive elements, I just enjoy using React more than the alternatives, even for static content. Instead of asking "what requires react", a better question is "what are the tradeoffs of using react in this situation". In my case React allows me to use Gatsby, a wonderful static site generator, and it also makes it easy for me to add any interactive content I want in the future.
My site will load fine without javascript, so it's hard to imagine react is slowing things down much (although if you've visited before the PWA will mess it up if you try to turn JS off).
For something like Wikipedia, time to interactive isn't that important (which is good, because lighthouse tells me that this page [1] has a TTI of 7.4s). First meaningful paint matters much more. I really disagree with the narrative that anything written with React is going to have a much worse user experience compared to the "old" stack.
[1]: https://en.wikipedia.org/wiki/Matthias_Hansen_House
