Calling cancel(reason) on a locked readable stream should not cause invalid state error. I cannot see anything that would say so in the spec and doing so causes incompatibility with the fetch spec.

Refs: nodejs/undici#1138 (comment)
Refs: https://streams.spec.whatwg.org/#readable-stream-cancel