Every time a custom entity or item field is created. It defaults in the results tab on a new item or transaction saved search. Is there an option to not have it default as a field in the results page on a saved search?

the creator should not have checked SHOW IN LIST on the record. Thats what makes it show by default. It can be updated

To prevent it just go to that custom field and unmark the show in list checkbox.

Thank you @C_Billings and @yagyakumarnag