I'm sure you think the person you're responding to is just an apologist for toxic behavior, and you might be right, but it's true that different behaviors are insulting in different cultural contexts. What is toxic is feeling that you are being treated as less than, with less respect than other people, and that is communicated through behavior in the context of norms. "Shouting" is a word that seems safely toxic, but that's because it's a pretty elastic word that adjusts to the norms of the people using it. I personally came from an extremely quiet household, and I am often asked to speak louder (by my wife, my therapist, by my friends when we're at a noisy bar) while my parents often used to complain in restaurants that they had to "shout" to make themselves heard. When they came to visit me, I had to choose restaurants carefully. Eating in even a moderately noisy restaurant could be unpleasant for them, because speaking loudly enough to be heard in that environment had unpleasant emotional connotations for them. Growing up in a family like mine no doubt contributed to my social anxiety as a young adult because I constantly felt that everyone around me was shouting in an alarming way, but I learned to look around and see that there was no panic, no hard feelings, nothing except people speaking at the volume that was normal for them.

Echoing and turn-taking can also vary dramatically by culture. My family were very strict turn-takers and did virtually no echoing at all. I have to go out of my way to echo back what people are saying, in a way that feels unnatural to me, so that they don't think I'm silently disagreeing and looking down on them. I also had to learn that people talking over the ends of my sentences is sometimes a calculated insult (as it would be in the household where I grew up) and sometimes just a cultural norm for them.

Business is ruthlessly doing away with all forms of difference, of course, and I will venture a guess that you, like me, belong to a group with a lot of power to drive this erasure under the banner of progress, power that we avoid acknowledging whenever we can. Shared norms can help prevent misunderstandings, but it is the sameness that helps, not the superiority of one particular norm about (e.g.) speaking volume, and the people who are helped most by shared norms are the most powerful, who have no adjustment to make because their own norms become the ones that other people conform to.

Chris Lattner is a smart and experienced person, and I have no doubt he judged his situation accurately. I just wanted to push back against your assertion that a behavior that someone might sincerely perceive as "shouting" is objectively toxic.