Yes, I found this question. But I think it is worth revisiting. Turns out I wasn't supposed to ask multiple questions in one. Oops. This post is about the amazon tag, and ones for the microsoft tag and the apple will come later.
Meta SO doesn't like the [amazon] tag, and requested it to be burninated. You can read their reasons here. I don't think we need the amazon tag on Ask Ubuntu.
Can anyone be an expert in Amazon?
I don't think so. One might be an expert in a specific Amazon product, say, AWS. But not all Amazon.
Does it meaningfully add information to the context of the post?
No. Other than saying that the question is in some way related to Amazon, it doesn't.
Is it on topic for Ask Ubuntu?
Depends on what specific Amazon thing they question is about.
Just looking at the top questions for the amazon tag, we can see that they all are different. Some are about Alexa. Some about Amazon search in the dash. Others about Prime Video. Each question is about something different, and the amazon doesn't add meaning or clarify the topic at all.
Let's burninate the amazon tag.