I have no technical data either way as to which is better. Logic says the bigger the load the more stress applied to the wheel/hub mounting point.
To me it makes sense for larger vehicles to have a tight hub fit as to support the load better. The OEM companies have a way bigger R&D budget than any of us, they probably set things up in the cheapest and most effective way they found.
That being said I would say the importance of matching hub size would depend upon loads carried. 1/2T used as a daily driver rarely loaded....eh who cares, 1T+ working everyday should probably get darn close.
My opinion for what it's worth.
