"Engineering around stupid is one of the biggest challenges an engineer has to deal with." That's funny and true but...don't forget, paying for lousy engineering is one of the biggest challenges buyers of vehicles of all prices have to deal with.
Seriously, my Jeep and Honda can count down remaining gas tank range to almost zero with accuracy.
Did you calibrate the fuel gauges on your Jeep and Honda by deliberately running out of gas? If not, then both manufacturers probably under reported fuel remaining as their idiot proof technique and is the only thing that prevented you from running out of gas when you were acting like an idiot driving around with zero fuel reported.
Vehicle lean is an issue for rigid tanks. While It is possible to make the bottom of the fuel tank funnel shaped to combat vehicle lean, that funnel shape reduces the volume of the tank. You choose, smaller funnel shaped tank that works at unusual lean angles, or a larger tank that gives more fuel to the non-idiots in the world. I'm glad Ford decided to go with a larger tank.