What is the correct way to use the ARRAY data type for image tags?

Question

PostgreSQL

You need to create a gallery with tags, search for them and top tags.
Considering PostgreSQL capabilities, it seems logical to make the tags field an array of varchars, let's say there is a 'images' table and a tags array field, everything is clear with the search (... tags @> '{fun, anime}'::varchar[];) .. .), but what about the top tags?
I correctly understand that if you create an index for 'tags', there will be no physical duplication of data?
Is such a structure really beneficial for this case, or is it easier to use the standard model, with a separate tag table?