This conversation has played out countless times at this point ... but to jump back into position for a moment - HRRR was due for a replacement, but it was hardly the most glaring issue for the park. San Fran and Springfield are huge, sprawling areas that completely effect the feel and experience of USF as a park, and that both feel, to be a bit uncharitable, very dead right now. Moes and the Duff Bar are still solid, and Fast Food Blvd gets business because of it's offerings and location, but generally both lands don't offer a ton, and certainly nothing on the level of Islands, Diagon, or Epic.
HRRR is a thrill coaster outside the walkable bounds of the park. It's very important, it's very visible in the skyline, etc. But it's also just one attraction, and essentially, a 1 to 1 replacement. Mid thrill coaster into a (probably) great thrill coaster. It won't meaningfully change the more fundamental issues with lack of attraction variety, screen tech reliance, and smaller scope theming. Tackling San Fran and/or Springfield could potentially tip the scales on all three significantly.
Personally? While I'd love to see all of these complete teardown / rebuild projects happen asap, I also would be relatively okay with smaller Dreamworksland-style projects to fix a lot of these dead areas. Ghostbusters meet n greet outside the Firehouse in New York; the BTTF Clock Tower retheme of F&F; making the San Fran Jaws theming permanent; giving The Simpsons Ride such much needed TLC; a new show in FFL.
I feel like none of those are huge unattainable goals, and yet, it seems like there is a lack of movement on any of them. Epic needed a lot of their resources, but Epic is here. Maybe we'll see something in time, that would be wonderful. But the line for a little while was "Epic is the priority right now". I am admittedly a little concerned that even after Epic, all the smoke seems to be indicating that USF is still not a priority.