A contact didn’t need to have both = 1 check makes sure that at least one of those columns is not blank.
Add a nice User Message and you’re good to go: Got multiple requirement groups? Here’s what it will look like if one of those is left blank I showed how to setup column validation for both phone numbers and email addresses and those can be used here.
However, the formulas I demonstrated automatically make those required fields since they don’t allow blank fields to pass validation.
To adjust those formulas just add an OR statement around the AND with an ISBLANK function.
There is a lot to choose from, I, for example, use