Mixed feelings. Grains of dirt, if not held in place by a thick or sticky lube, should get flung off when riding at high speed, or turning the crank backward even faster, at the tight bends at the rear derailleur rollers. Heck, I use one of the thicker lubes, 90 weight gear lube, and fresh after lubing, there is still some flung onto the rear rim, so plenty of centrifugal force to do that. (Perhaps I should wipe down my chain after lubing.) But any dirt that remains, I'd wonder if any merit to wiping down. My lube gets kinda pasty after about 600 miles, but I don't think wiping it down will improve things, what matters is the lube between and inside the links. I ride in dry and faily clean conditions. The black pastiness of lube after about 600 miles, is due to very fine suspended metal particles in the lube, forming a (colloidal?) suspension. I know this because, after using an on-bike chain cleaner with mineral oil, I dip a magnet in the fluid and all that black sludge gets pulled right out of solution, sticks to the magnet. My point being, dry lube should accumulate less dirt, and either dry or wet lube, I'm not sure the merit of wiping down the outside. Unless it's water and you're trying to speed drying by reducing the amount of water. I'd be curious if any of the lube or chain makers have done tests of chains in various states, wiped down versus not wiped down.

Thank goodness for on-bike chain cleaners, they really speed things up. However they do nothing for the big pasty buildup on the derailleur rollers, cogs, and chainrings. I do miss how clean those all stayed when I wax-lubed.