In your SharePoint Online pages, the People web part only had a small and large setting. This was, to borrow a theme from Goldilocks, either too cold or too hot. Now you have a Medium setting, which seems to be… just right. 🙂 Here’s how it works…
I created a page section with three columns, and put the three different People web part sizes in each column. The Medium setting (the new one) is in the middle. It’s a mix between having no description (the small setting) and having 255 characters of description (the large setting). The medium version allows for just 50 characters, but obviously takes up a lot less space on the page:

And here’s what it looks like once it’s published:

This is definitely an improvement when you want to provide a bit more information, but not take up a lot of space on the page.