JSX and PHP are actually seriously different. When you break out of PHP, you're just outputting text to standard output. When you're using JSX syntax, you're constructing Javascript objects that can be manipulated using standard javascript techniques. Anyone who believes they're comparable seriously doesn't understand the task that is before them.
My reading of this thread is that people are comparing JSX as a templating language to PHP as a templating language, splicing PHP <? ... ?> into HTML like how we have { ... } in JSX. At the end of the day React lets you write a function that returns HTML just like a PHP file.
