Carpet prevents enchanting table from increasing level requirements.

Surrounding an enchanting table with carpet prevents it from recognising bookshelves on the same level as the carpet.

This was marked as "Solved" on an older issue, however it seems to still be present in the game as of version 1.20.2 !

To recreate this, simply place an enchanting table and surround it using carpets, then place bookshelves around the 3x3 area created previously(as in enchanting table + carpets). You should notice the enchanting table does not detect the bookshelves.