https://en.wiktionary.org/wiki/contentious "1. Marked by heated arguments or controversy." There are heated arguments about this (among laypeople). The people arguing heatedly happen to be wrong, but the dictionary doesn't say that the heated arguments must have merit, only that they happen.

BTW, your "There is literally no credible argument why 0 would be considered odd." suggests that you didn't read the linked Wikipedia page and didn't look at the results of the Mastodon poll. Take a look what actual laypeople self-report about their position on this issue.