Its hard to know, I for one tow a 2500lbs tractor around a few times a year, or a load of mulch, or take it into situations where I need 4x4 high clearance.

But OTOH, probably 90% of the miles on it are driving around "to the mall" or work.

Could I rent a truck every time I needed one? Probably, but it would probably cost me another $1k+ a year or so, be massively inconvenient, etc.

OTOH, a lot can probably be done to improve the efficiency of normal trucks being used in commuter situations. Hybrid/etc style vehicles are probably just fine for my use case, since I already have the baby motor in it. Is it a bit slower/etc when I'm towing, sure, but it gets the job done.

Why is that relevant? Do the people who actually need to tow no longer matter because some people don't?

That doesn't invalidate anything. Most around here haul stuff and actually use them.