The weird balancing of plates I have seen developers do to not talk to each other amazes me. I often have to remind frontend that we are on the same team as backend and we own the technology: if we need an api to behave differently, let's make that happen, not code around it. Similarly, I have to tell the backend team that the things they find frustrating can be automated, processes can be changed, and we can talk with ops and platform teams to come up with solutions instead of coding around it.

Yes, but when you do manage to get people to "say what they mean" I had the following response from a frontend bloke (me being on the "backend" side, even though I never refused to work on frontend per se): "I don't like you and I don't like your stack, I want to make decisions regarding frontend without consulting with anyone, I want to get promoted for running a team which overcomes any hindrances related to either how the product actually works or that human collaboration requires communication."

It is not about "nog being able to collaborate" - it is about refusing to do so.

On the other hand, people can't possibly talk to each other if they are always in a meeting.