The single biggest issue I've noticed is that body language communicates a lot, and in remote environments you cannot see this. You don't feel at all invested in the other person either, and I've noticed people multi-tasking instead of listening to what the other person is telling them - often followed up with a "Sorry, I missed that. Can you repeat it?"
As another example, I've worked with some people who are quite confrontational and dare I say, aggressive, on camera, and have raised their voice a couple of times in the past. This same person has very different interactions in real life, a lot more empathy, where it becomes apparent the other person is in fact, an actual person with emotions.
The disconnect is real indeed, and in my experience mostly solved with company get-togethers. After the first get-together, people have a much better idea of other people, vibe better together and thus have a lot more empathy as well.
That said, if a person is unable to conduct themselves professionally whether it is via a video call or not, I think it has nothing to do with remote work and all to do with that particular person being bad to work with.
As another example, I've worked with some people who are quite confrontational and dare I say, aggressive, on camera, and have raised their voice a couple of times in the past. This same person has very different interactions in real life, a lot more empathy, where it becomes apparent the other person is in fact, an actual person with emotions.