https://wccftech.com/2021-macbook-pro-no-egpu-support/

Picking up a notebook computer with a Thunderbolt 3 or Thunderbolt 4 can have a bevy of advantages, including the option to attach an eGPU for that extra graphics performance boost. Unfortunately, in the case of Apple’s 2021 MacBook Pro family, that option is not there, despite the 14.2-inch and 16.2-inch versions carrying the supported hardware for it.

The Thunderbolt 4 ports belonging to the 2021 MacBook Pro models can deliver a maximum bandwidth of 40Gbps, up from 20Gbps from Thunderbolt 3. Despite the speed bump, there is no eGPU support for the latest portable Macs, and Apple is yet to provide an explanation for it. The company did not bring eGPU support to the M1 Macs last year either, and compared to the M1 Pro and M1 Max, the M1’s GPU performance comes nowhere close to the latest custom chips.