Not a MH, but TT and now 5er driving. Over the years the time on the road has changed and it also depends on the circumstances, length of trip, and length of stay.
In the past, when the kids were still little, we'd travel for hours on end to reach the destination point. Long driving days. When you are young yourself, you can do this.
When the kids no longer camped with us because they started their own lives with jobs and college and military service, and everything else, my wife and I learned to slow down. The "rush, rush, rush" wasn't so important any more. The entire travel event was just as important as the destination point. In other words, the "journey" was just as fun (if not more) than the actual destination point.
So, for those week long or 2 week long trips, we pick the end point destination spot, and then break the number of stops along the journey so we don't have to spend more than 6 hours actual drive time on the road. This built in nice cushion for stops along the way, restaurants, and side attractions that grab our attention.
As we've gotten older yet, that drive time is now about 4 hours, because we just enjoy monkeying around so much on our drive. We stop a lot. We'll drive 30 minutes and find another interesting land mark, another interesting restaurant, or need to stop for the dogs to potty (or us). We stop at almost every rest area on the interstates, just to stretch a bit, gab another snack and drink, use the facilities, walk the dogs and then move on.
Now granted, we do have exceptions also. April 2019 we traveled from South Carolina back to Indiana in one stretch and drove through the night because something came up and we needed to get back home. So, we can do it if we need to, we just choose not to if we don't have to.
The older we get, the more we slow down and enjoy the journey and the destination points seem to get closer and closer now.