I don't understand this. You could build up the template using jsx exactly like you could otherwise. For instance, I could put that in a variable and then use it in another template via {}
You could, but it's unintuitive (in my opinion) to do so -- which was the parent's comment larger point. You're not doing anything different, and to an extent the latter is actually lying about what's going on (you're not writing HTML). I also lose a certain level of tooling by doing it the JSX way. Why try to mask what you're doing? Why make it harder for your tools to help you out?
I guess I haven't felt this pain that you've felt. I'm satisfied with my tooling and feel that small components help keep things very clear and focused.