When I released my app 8-years ago, I thought support would be my most hated part of releasing a product. To my surprise, it was one of the most rewarding parts, I met some great people via email, some I will visit one day.
But support has its ugly "toxic" side as well. This is particularly prevalent in 1-star reviews for trivial issues. All the reviewer sees is a box to vent their thoughts without considering that there is a real person on the other side. But I'm a real person who cares and some comments do stir bad emotions. This has brought some of my lowest and darkest days of app development.
Sometimes I will make contact with the reviewer and as soon as they get to know me as a real person, they are friendlier and more respectful.
The faceless nature of the internet causes people to treat others poorly. In the real world where we meet people in face-to-face, our initial and natural position is to treat each other with respect.
So here are a few ideas: 1. imagine a person, someones face, not a textbox, website or company - add a persona to him or her. 2. Ask this simple question "Would I treat or talk to someone (my friend) like this in real-life?" 3. Would you be proud of the way you're conversing if people you admire were watching, e.g., respected colleagues, friends, parents.
This will change the way you write.