Should I create a separate referenced table or go with serialized data in a column?

I have a table with name app_client with the below fields: > id, user_id, name, age, phone, gender, **related_entities_json (long text datatype)**, > created_at, updated_at I have 200k+ records in this table and I found that the size is mainly increased (7 GB ) due to related_entities_json field. So I want to know if should I move related_entities_json to a separate table? And then access its data when needed? I don't want to open another question for this so I would also like to know if this will increase performance during fetching/inserting data. Entry in related_entities_json from a row: https://pastebin.com/y4XDCK4Y