Personally, I always found the idea of a rival Ghostbusters company to be a great story within the franchise. Maybe that's because it was the first episode of the animated series, or one of the best IDW storylines (I love to hate Ron Alexander), but I just think that'd be a lot of fun to see on the big screen.
It's a great way to delineate how the tech works, not get bogged down in a down-and-out-civilian story line for the first half of the film like usual, define what it is people like about the Ghostbusters, give us some fun villains, and provide plenty of opportunities to see ghosts actually being busted instead of one first bust and a boss battle.
Updating that premise for this era would be, as Pitch Meetings say, "super easy; barely an inconvenience." Who ya gonna CALL? Bro, this new company has an app. They're disrupting the field. They're taking an old technology and repackaging as something totally new while playing games with regulators and hiding their misdeeds (look no further than Uber's "
greyball" program for a blueprint).
Their tech is new and modern and sleek... and probably not as benign as they pretend. The antagonists could be human, ghosts in disguise, disgruntled cultists, a robot or drones... all of the above. There's just so much fun to be had with the premise. It's familiar to us hardcore fans, but isn't a retread depending on how it's done. Each character can get a foil to bounce off so we can quickly establish who everyone is and what their values are without fixating on a deep dive character study so we can see action and comedy unfold. And it's a fun way to acknowledge how times have changed while underscoring why we love the things we love while also opening the door to some updates.
Winston restarts Ghostbusters, other titans of finance and tech gurus see an opportunity to enter the field, and all hell breaks. Make it more than one rival company so there's too many busters and not enough ghosts. How does an unscrupulous company get around a spook shortage? Let out some of the spirits they already capture and bust them again and again.
Every time a ghost is released and trapped again, they adapt to the technology to the point where it stops working. It could even be set up where the blinking containment unit light at the end of Afterlife is the grid failing for that reason. Phoebe's got to travel to New York to address the issue the and keep the containment unit working, so our crew is on to the ongoing issue of the technology having to stay ahead of the ghosts adapting. But rival crews won't have that sort of longitudinal data, and will make the issue worse with new flashy tech that hasn't been vetted properly.
Ghostbusters: Disrupted