There are no PoW competitions. But I will be happy to submit once there are.
The only thing left is to note that your statement
"PoW blockchains are inherently vulnerable to QCs"
only applies to PoWs where a huge range (at least billions) of nonces is searched
(by one miner in one block interval).
If you "solve" PoW blockchain vulnerability by making mining centralized then I can't accept this as a solution.
Cuckoo Cycle reduces the gap between commodity and custom hardware by being memory bound, making mining less centralized.