I think what may hold back HEA from ever returning is simply ego.
Fireworks directors, executives won't want to bring back an old show they replaced unless they can put their stamp on it. I absolutely think if it returns, it will be modified. Main Street projections, add in a song (+Encanto) - seems like our only hope...
I have been touting the AH 50th party between January and August for some time now. But
@disneyglimpses idea is best. Make HEA the fireworks show for those party nights. And while that's a great idea, it's probably just too close from "retirement" to return.