There is nothing wrong with choosing the simpler option.
To prove to you, I used the same code Xena used in the article and reproduced it with React: https://codesandbox.io/s/mutable-water-y385q?file=/index.htm...
No compilation. No build. Nothing. Same API too.
What you're proposing is essentially saying "look, it's easy to fly, here's how you do it in python":
import antigravity
def main():
antigravity.fly()
if __name__ == '__main__':
main()`import { g, h, x } from "/static/js/xeact.min.js";`
Please see her source as I have used the same source, sans her library, to replicate it with React.
Instead of importing from "/static/js/xeact.min.js", I am importing React. There is literally no other difference.
> can be directly copy-pasted in your business javascript code
Why can't you do the same with React? You literally can copy-paste entire React code in your HTML. Nothing stops you from doing that. Doesn't matter if you import it as a file or inline it in your HTML. It is plain old Javascript at the end of the day.