MH manufactures don't make tires, they leave that up to the tire manufactures and buy what fits their platform. I would say that the correct inflation data is the responsibility of who made the tires as they have done all the research to keep their products safe and reliable. Mine was delivered from the dealer over inflated even from the placard posted by Fleetwood. My coach was all over the road. I weighed it and inflated per the tire mfg graph plus about 5 lbs to adjust for cargo variations. Now rides like a dream and is within 8 lbs of what is posted on the MH placard.
If the tire mfg has a printed graph depicting weight vs pressure it is probably a prudent decision to believe it is correct. I'm sure if inflated correctly ( per the data) those claiming it's going to blow hitting a chuck hole are being chicken littles. Not inflating per the weight recommendations on the graph ( meaning actual under inflation or over based on the weight) can put the tire in a condition that could cause problems.
Sure filling it full of air will probably save you a few cents in fuel and perhaps better wear. The trade off is handling and beating the snot out of your suspension and every nut & bolt and nail on the rig, " and you". Me, I'd rather enjoy the ride.