Exception in displaying the avatar of the article author

Hello, my website is currently using WordPress version 6.3.2 and the theme is Twenty Sixteen.

I found that if there are only articles published by the same author on the website, the article author’s avatar will not appear in the article list on the homepage of the website.

If there are articles published by different authors, the article list on the homepage of the website will display the author’s avatar of the article.

I have changed other background themes but did not have this problem. Even if only the same author publishes articles, the article list on the homepage of the website will still display the author’s avatar of the article.

It seems to be an obvious problem with Twenty Sixteen. Has anyone solved this problem?

Thanks!