An additional read-modify-write cycle out to whatever memory is storing the en-queued descriptors, potentially for every packet ingress? And what happens if you hit a don't transmit packet on your next sample? Stall the pipeline and try again?
At best it would halve the worst case throughput of a memory bandwidth bottlenecked system (e.g. 10g+ packet forwarding engines)
Compared to RED (just needs a RNG and a fullness counter) and SFB (whos state can be made 'arbitrarily' small without compromising the queue capacity, and so can be kept on chip) this sounds pretty unfriendly.
Of course, not an issue on some small software driven router handling only a few tens of megabits. but most of those devices could also do real flow-aware queuing which was far more fine grained than CHOKe.