I think this can be very faculty-dependent. At my residency institution, when I was a PGY3, I got an inpatient consult on a patient who had already been seen and had recommendations made by a local PP doc, who was an alumni of our program. When I told my attending this, and asked if we still needed to see the patient, he scoffed and said "of course, our job as the academic center is to render an informed opinion that a local 'doc-in-a-box' isn't able to do". Spoiler alert: his opinion was the exact same as the PP doc.
Another time, a few years later with a different attending, I was seeing a consult who wanted to go to a PP doc closer to their home. That patient had a family member with them that day, who had been treated for an oropharynx cancer by that PP doc 6 years prior. She was still cancer-free, and the only long term side effect she appeared to have was some neck fibrosis. When I told my attending this, he goes "can you IMAGINE being treated for head and neck cancer at that place?!? I can't, what a great way to die". I wasn't quite sure how to respond, given the evidence to the contrary sitting literally in front of us.
These negative opinions of PP physicians were, of course, passed along to patients, either subtly or, usually, blatantly.