Would you not buy a 1/2 ton based SUV at all because it wasn't able to get 28mpg on the highway?
Would only being able to achieve 20mpg on the highway change your mind about needing the space and utility from a 1/2 ton based SUV? Also depending on the area you live in, diesel could be significantly more expensive than gas.
What did you use prior to GM putting the LM2 into a 1/2 ton full size SUV in 2021?
I'm really interested in seeing GM's LZ0 in a 1/2 ton full size SUV in 2024 but the 6.2L gas is fine as well. Although I could see the LM2/LZ0 being more of a requirement for someone that is going to be towing lighter trailers frequently up and down significant declines. The exhaust braking function in tow/haul mode would be incredibly useful. But that's about the only use case where I may require a diesel because the rest is more of a running cost problem.
That was my point.
Currently my family is in a Honda Pilot. We want a 1/2 ton based SUV for both the interior cargo/people volume and the towing capability. I would prefer to own either a Honda or Toyota product, but since Honda doesn't have a 1/2 ton SUV, the first rig we looked at was the Toyota Sequoia. It didn't bother me that it has only received minor updates since 2008, but what did bother me was the ~13mpg we would be getting on a good day with the 5.7L V8. On top of that, the cargo volume behind the 3rd row is not much more than what our Pilot offers. I waited to see the redesign of the Sequoia and that put the nail in the coffin for us. No significant gain in cargo volume and solid rear axle makes the 3rd row seating ergonomics as bad as the previous generation Tahoe.
The next rig we started researching was the Ford Expedition Max. There's a lot of things to like about the interior of the Expedition, but after spending a few months on the Expedition forums, Ford has some serious problems with the cam phasers on the 3.5L EB and in general it seems like there's more significant problems people are having with the Expeditions.
I'm not looking at the Grand Wagoneer because I'm not going to spend that kind of money on a car. That leaves us with the Yukon XL/Suburban platform. GM certainly has their issues and isn't the perfect car company, but they have the biggest 1/2 ton SUV on the market with an engine that will get better fuel economy than our Honda Pilot.