Regular users can use to Edit filters and Delete Filters only if they have access to the CTX_PORTFOLIO application and CHANGE Privileges on them. If they do not have access to the CTX_PORTFOLIO application, they will only see the Use Filter option
If you have access to the CTX_PORTFOLIO application and CHANGE Privileges on them, You will see the Edit Filter and Delete Filter options also. A developer should be given access to the CTX_PORTFOLIO application