Batching won't solve any problems you might think it would solve. The real world is continuous. Because of this, everyone is incentivized to wait until the last

Batching won't solve any problems you might think it would solve. The real world is continuous. Because of this, everyone is incentivized to wait until the last possible millisecond (or nanosecond) before the auction to submit bids so the incentive to build fast acting systems remains. There are other problems as well, like how to deal with bid/ask imbalances at auction time.