They don’t want to: it helps deuce demand for the iPhone via the macOS/iPhone tethering integration, and for calls taken via FaceTime.

They could if they wanted to, I’m a bit surprised that they didn’t add it with this big new MBP generation.

Especially now that they have their own modem and wouldn’t need to pay whatever royalties Qualcomm would demand, which I’ve read are based on the device price and would get very high on a premium laptop.