It depends what the product is. If you're trying to build another Zoom (which I gather from the "rooms" question), yes, it will take quite some time. For one thing, the mesh topology of P2P won't scale up beyond a handful of users, so you'll need to make it client/server. And besides time-consuming, that starts to get operationally expensive. Decoding, compositing, and encoding high-resolution video streams in real time take some processing power.