The classic editor’s limited text editing capabilities led to heavy reliance on meta boxes for complex content types. Events, products, and other custom content required multiple meta boxes to handle all necessary fields.
This approach creates poor user experience – working with meta boxes feels like using a spreadsheet rather than a content editor. Users can’t visualize the final output until they preview the frontend.
Meta boxes also encourage storing content-related data in post meta rather than proper content fields, leading to performance and architectural issues.