Crippled BCM4387 in MacBook Pro M1 Pro
Why is the 2021 MacBook Pro M1 pro crippled to 80 Mhz channel bandwidth and no Wifi 6E even though the chip BCM4387 in it supports both 160 Mhz and Wifi 6E?
The 2021 MacBook Pro M1 Pro shipped with support for WI-Fi 6, not Wi-Fi 6E. That information is in its Apple Technical specs for that model, or even from EveryMac. According to Broadcom specs, the BCM4387 supports up to Wi-Fi 6, and the BCM4389 does provide Wi-Fi 6E and 160 Mhz channel width. Even the Broadcom press release announcing the BCM4389 as the world's first 6E chip. More on the limited adaptation of 160Mhz channels.
Broadcom does show HE160 support in the BCM4387 chip and I just powered up my 2021 MacBook Pro M1 Pro running Ventura 13.6.7 and observed momentarily it connected to Wi-Fi 6 at 5Ghz and 160Mhz channel width before changing to 5Ghz and 80 Mhz. Then again, it just dynamically shifted to 160Mhz while I was watching it and then back again to 80Mhz. If you were expecting the BCM4387 to lock onto and hold a 160Mhz channel width then that is not going to happen. My router is a firmware current Synology RT6600ax.