Differing isn't a sign of rationality; differing rationally is. Being open minded about a thing with no sure conclusion is a sign of rationality. Being open minded about whether or not 2 is greater or less than 2 isn't. So as with most things, it's a case by case examination. Shallow is a bit like beauty absent a reasoned standard and proof beyond the declaration of it.
Starting? Is it fair to contrast the point before you hit send with what everyone else experiences from you thereafter?
You sound fairly young to me. Obviously old enough to appreciate that positions should be reasoned through and argued but you don't appear to be old enough to be comfortable doing it. I've had a number of truncated conversations with you where I've noted your unwillingness to argue or present particulars and support, though you complain quickly enough on the point.
See, that's young. It isn't really a rebuttal, doesn't establish the unreasonableness of the treatment you're complaining about or establish your part as the fairer, as presented...if you take an unpopular stance a good many people will take exception. I've been at the center of disputes with four or five strongly held and contrary opinions on a point. That's how it goes if you support an unpopular part or set out a strong opinion on a divisive issue. It shouldn't surprise you or catch you off guard. And if it doesn't, it shouldn't bother you. You knew it going in. So be prepared to argue and answer on points, sustain your opinion wherever possible with objectively demonstrable authority. That sort of thing.
If, instead, you complain about your rough treatment, fail to answer rebuttal, to offer objective authority, etc., you only have yourself to blame for what follows.