Door slamming is less to me in situations where the door slammer is clear up front and why with warning and why and both sides are very clear about the basic facts.
My door slammer in a hypothetical example may not think I treated her well. I may disagree and think so. What matters to me is that can we agree on the basic facts of the situation. If we both can agree on rhe basic facts I can live with that. What's more challenging is if a door slammer assumes too much without discussion and then door slams based on incorrect and non-agreed upon facts. Facts matter.
We can disagree on things and go our separate ways as long as we are very clear on facts and can agree about the facts. How one feels about facts is different from the facts themselves.
Door slamming to me is a lot about being unclear, leaving lots of unanswered questions and issues on the table. There is certainly much more tolerance in situations where a door slammer is very clear and upfront, not hints, not signs, not guesses.
At the very least we can agree that some door slamming is bad, negative unhealthy and unproductive. In other situations, it would be a discussion for me to even decide if something is a door slam or not. Door slam the words to me are severe, extreme. Slamming a door literally is often not a good thing. It is an extreme action, to physically slam something shut. That is how I approach it.
To me door slamming is all about one person wanting to stay in communication and the other one not wanting to do so. I think this statement is important. There is nothing mutually agreable or mutually beneficial about a door slam. I approach life in a mutually beneficial way unless there is an extremely abusive reason from the other person not to do so. Disagreement and hurt feelings are not enough for me to not approach life that way. If you are upset and have hurt feelings and want to leave, fine. But taking one day to meet in person is not too much to ask before leaving. Getting facts straight to make sure it is a good decision, clearing up loose ends. It's basic human decency. Only in Abusive scenarios would I understand not doing so, ans even then I believe it is important to have a clear message sent and why. Relationships are always about two people, not one.