Creating an override is basically just providing a placeholder for a value to be injected via React Context. I view this as a form of dependency injection. Contrast this with how this would be done in vanilla Playwright with reading it from a query param or exposing a global to call page.evaluate on which is more along the lines of forcing test code into a component.
Note that if you needed a specific reference in an override there isn't a good way to get that via Playwright, consider this silly example:
Note that if you needed a specific reference in an override there isn't a good way to get that via Playwright, consider this silly example: