comparison of scythe vs. a manual push mower (vs. gas/electric mower)

hello, i have seen YT videos of races between a scythe and "brushcutter", and a scythe and a gas mower, but are there any videos (or science/data) of scythes vs. manual push mowers, in terms of relative speed (obviously grass height'd make a difference). similarly, anybody seen videos or science of races/relative speed of manual push mowers vs. conventional gas/electric mowers?

(and this is for those who think "nice-looking lawn" or "that grass needs to be cut" of course)

Manual reel mowers were actually originally intended as grooming tools to be used after mowing with a scythe! While it's very possible to get a "lawn-perfect stubble" with a scythe, it requires much more skill and often a blade tuned just for that use to achieve one reliably, and so reel mowers allowed common folk to do a "hack job" knocking down the tall grass with the scythe and then go over it with the reel mower to trim the uneven stubble to a uniform length. This is why they perform so poorly on taller grass--they were only ever meant to handle stubble left by the scythe, and were especially used for spaces where people would be engaging in activities of some kind, such as lawn games, English style gardens, and so on.