Current problem
While P2P calls reduce bandwidth costs for the server, clients expose their own IP to others clients.
The average user isn't always conscious of the privacy risks linked to that, and doesn't necessarily uses a VPN either.
(Alternatively, bad actors could convince people to use P2P calls under the pretence of the perks, tricking them into revealing their IP.)
Proposed change
Adding the option to identify "trusted" contacts for peer-to-peer calls (e.g. people known in real life) for which the risks to privacy are lower. P2P calls could then be limited to those.