I have been dealing with my local Chevy/Subaru dealer for >30 years. I have bought a half dozen new and used cars/trucks from them over the years, both brands, but I have also entrusted them with GM vehicles purchased elsewhere. I have no horror stories from the service side. In fact I highly recommend them! (The body shop is a different story, but they have improved. Fortunately (KoW) I have had rare need for their services.) The service dept. is not perfect to be sure, but any mistakes they make are corrected to my satisfaction and immediately. I am on a first-name basis with them and probably can invoke a few favors, like a loaner vehicle on occasion, when needed. There's a good reason I have stuck with them for so long!
I'll be at a real loss if this dealership is one that GM needs to close. They probably could not survive on their Subaru business alone but might have to try.
Since many are quick to complain, I again feel a need to speak in the positive when warranted, and this is such a case...