The way to 'question' ebay policy is to use the suggestions link. You can find it on the site map.

I doubt very much if that is a policy ebay will be interested in changing.

Often a buyer or seller just wants the phone number so they can confirm the seller is who and where they say they are.

Especially where pick up items are concerned a prospective buyer may want to ask more in depth questions than can be fitted into the limited number of characters allowed in a contact email.