set value default for operator

Hi , i'm trying to change the competitors page in opportunities - followed the guides but without success. i dont really understand why - followed this guide:
https://docs.oracle.com/en/cloud/saas/sales/oasal/make-changes-to-competitors-pages.html#Competitors-Pages-and-Navigation
no matter what change i do to the fields - it doesnt effect the page. the below is the page i want to change.

basically i want to show by entering this page all the available competitors - so sales dont guess what competitors are available in the system.
so if i can't change this page - i want to set the Operator for Competitors name to "is not blank" by default and ask them to press the search button.