They also mention that those tests were made in the best case scenario (disabling noise correction, etc. for the sake of speed) with the best performing mobile,

They also mention that those tests were made in the best case scenario (disabling noise correction, etc. for the sake of speed) with the best performing mobile, and by following Google's low latency guidelines. Most Android apps don't have the first two luxuries in the general case, and (apparently) don't bother with the last one, thus the much higher latencies in practice.