Multi-user Categories

Hello all. I am trying to create a multi-blogger wordpress site. The main features are already there, meaning each user has their own page and RSS feeds built by default which is great. However for organization I want each user/blogger/author’s posts to always be in their own category. For instance Blogger 1’s posts should always be in the category “blogger1” etc. I could manually have each blogger always change their category from “Uncategorized” to “bloggerX” but this is not very smooth. Does anyone know of a way to either change a user’s default posting category or what would be even better would be to have every user’s post automatically in their own category that they cannot adjust as well as being able to pick an additional category.

This is much more organized as well as this way I could automatically have the newest post from each author (category) placed on the page in my theme. The only other way I could think to do this would be like above make them always manually choose their own category or I could import their RSS feeds but that seems like overkill. Any input is appreciated, thanks!

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