I frequently hear this sentiment, yet in my country I struggle to find evidence of more than a few ms of wifi vs cabled connections. Whereabout do you live that this is such a huge issue? Is it a large, dense metropolis like Beijing or Singapore?
Due to bad engineering, a WiFi chip can either be scanning or transmitting, and background location tasks can request a WiFi scan at any time. Depending on your OS and what else you run, this can cause stutters in the 250ms-1second range.
once you have to scroll in the ap-list there is a very good chance that you are contested on air-time because some neighbour is active on any given channel. [0]
add to that interference from non-wifi or other unclean rf-equipment like babymonitors, wireless doorbells or bluetooth ... 2.4ghz is quite crowded, 5ghz is crippled by a wall...