If we did, what would be the benefit? The majority of us can depart with 125M RVR already and you really need 75M to taxi, or are you suggesting "Auto-taxy" as well? Over my lifetime (see panel to left) I can probably count the days where visibility has been less than 125M on my external digits, ie less than 22. I'd suggest that the reason we don't is that there is no economic benefit.
PM.