I think the most realistic hope for any kind of new major headline coaster attraction would be the aforementioned Boss plans being signed off on, as you say. Not only was it apparently a done deal before the pandemic happened, but it accomplishes the two-fer of having an attraction that would juice the turnstiles AND makes it so a very expensive (and rapidly aging) asset is refurbed and becomes much easier and cheaper to maintain going forward. Chatting about SFSTL with non-enthusiast friends, it's amazing how often the Boss comes up unprompted as being something that's avoided at all costs due to the headaches it creates.
Anyways, back to this coaster. Two of my daughters are the target demo for this coaster and are excited about it. I would guess this ride, when complete and operational, is going to over time be one of most ridden rides in the park. A junior coaster was desperately needed here and I commend them for doing it.
However, the "theme park dough" spent this year in the family budget went to Silver Dollar City for spring break tickets (never been there, I'm pumped!) and King's Island (adored the park when we went last year). If it sounds like the SFSTL has a better year this year on the ops/staffing and other stuff, maybe we will snag some cheap one day tickets later this year so the kids can try out the new coaster when it opens.