I’m not saying it’s a conspiracy like the guy you replied to, but it’s generally considered correct to include 0 on graphs like this to show proper scale. If I had submitted a paper with this graph in grad school, all of my reviewers would have kicked it back.

If you want to get technical, it's only standard math if there's a symbol indicating the scale doesn't start at 0. Data is used like this all the time to misrepresent reality and yes, it's considered "normal" to do things that way.