Hi. I understand the UX isn’t perfect, but it’s not possible to change it to a text box because then the logic connected to it would not allow selecting an existing Organizer. Additionally, the form input needs to connect to the Organizers post type to fully work instead of just a text field within the Event’s information. In other words, it’s linking 2 post types (Events and Organizers).
Some site administrators think they want to disallow selecting an existing Organizer, but that can lead to many duplicates if the same user adds multiple events.
Similar story for Venues.
Please let me know if you have any follow-up questions on this topic.