[starkparker]

Because it's not about React (or about XML, looking at the sibling reference to E4X not being mentioned). It's about JSX. Just like your article doesn't mention JSX, and the sibling article on E4X calls out all the ways JSX fundamentally diverges from E4X, and so they "feel rather incomplete" in the context of comments on a post about the origins of JSX as explored through making a parser for JSX.

[theultdev]

The JSX syntax was inspired from work on XHP, not E4X.

Seems strange to focus on E4X when discussing the origins vs the actual origin.

Just because E4X is somewhat similar doesn't make it the origin.