The top speed of a family suspended is like 30mph. The average speed, much less. Much less.Yes you can see the neon signs on Rock'n Roller coaster but you by then so quickly I feel they don't add much to the ride.
Yes Monsters Inc will be slower but you still be moving at a decent speed that you won't really see it
You're telling me the human brain can't process a scene when traveling at that speed or more realistically at <12 mph?