Sorry, still not convinced.
Apple states that a 1 minute video at 4k60 uses an average of 400MB (480MB for slow-motion)
Youtube video measures write speeds above 1GB/s in both configurations which leaves a lot of overhead, and so does the read speed at a minimum of 250MB/s.
I agree however that when moving and copying it will obviously help. I'm just saying that when it comes to me I can live with it taking a little longer since I cannot justify getting a larger storage based just on the speed (that is on a phone of course).
Yeah and really, even if you take 4k video, just optimize your photo storage and let them sit on the cloud.