I can have cloud widget for both tags and categories 1:1
I can have counter how many posts in category 0:1
I can have hierarchy of categories 0:1
It’s easy to create new tags, just separate them with comas 1:0
I can choose from tags from the “most used tags” cloud 1:0
Categories are less chaotic 0:1
So categories win 3:4.
So i’ll use categories only for tech, nontech, polish, english and tags for everything else.