This update was not about decreasing the hashrate of the network, it's about decentrilizing it. That was the goal.
As things were with ASIC miners,
1) Only the few people who would be able to afford their cost would buy them
2) Those ASICs that were not bought could be used by the manufacturer in a huge farm, though there's no way we can know if that happened
3) If the manufacturer of these ASICs decided to put a killswitch inside the miners, they could shutdown the whole network anytime and make theirselves the sole miner.

The aboves are the main reasons people are against ASICs in general though, not just the ETN miners. Sure there are a few positives, as a more "secure" network against 3rd parties, but for me that doesn't offset the risk of providing to someone from the inside (the manufacturer) the keys.