Not too long ago I opened a dispute with Ryanair about what I thought was quite obvious their own issue for which I should be refunded (I provided screenshots and everything). I've reached out to their customer support expecting to raise a simple issue that should result in a quick solution on their end. I was shocked to see their support behaving in a very defensive and completely dismissive way that resulted in a 2 hour long support case that didn't really fix anything (they still have the same bug on their website, and I was not refunded). These guys basically upgraded me from 'slightly annoyed' to 'never again will I fly ryanair' kind of customer.
In another case, I've reached out to an online chocolate vendor to point out an issue I had with their shipping carrier. I knew it was not directly the vendor's fault, but this being their only shipping method I figured they should be aware as it is a constant problem. These guys acknowledged my frustrations immediately and even offered a symbolic gift card as a way of apologizing for an issue that they can't really fix any time soon. I was generally happy to see them even acknowledging my problem, and in turn completely understood that this was out of their hands. I continue to be their customer even though the shipping is still a pain.
I also have a local ad to help my father sell some stuff he makes by hand. As its a hand made thing that he makes in large quantities, mistakes happen every now and then and I get complaints. I try to be understanding of every issue they raise and offer urgent refunds/replacements to anyone affected. Even though people get pissed off they didnt get what they expected, everyone responded much better if I used similar methods of de-escalation.
People are often (and understandably) very impulsive and rude when they feel they are being wronged. We should try to be more understanding of these emotions and work towards solving the issue instead of taking it so personally.