Of course one should temper expectations no matter how these meetings go but these meetings aren't helpful solely for the reason of figuring out your chances in the program. Especially for people unfamiliar with US admissions, there are deep gaps in knowledge that home institutions can seldom help with. I had one professor from undergrad and master's combined who had a us doctoral education so these meetings are great way to familiarise yourself with the process, understand what kind of mentorship is being offered and get sense of if the program is a right fit. I had really good conversations with POIs and sure I wasn't admitted to every single program where I had a good meeting but those were extremely productive conversations about sources, possible directions where the project could head towards and intellectual environments of diff spaces so I wouldn't outrightly say don't reach out at all, i think like most aspects about this process it's a case by case decision.
