You're going to get some biased opinions based on what flavor of Kool-Aid everyone is currently drinking... I currently have GMC 1500 with a 6.2, and looking to get rid of it. I bought it new and have 123xxx on it. I know of 6 people in my small circle that have had 5.3/6.2 motor rebuild or replacements due to the on going lifter issues. Anywhere from 50k-120k before a lifter gets stuck. I would look at the last 12 years of AFM related engine failures prior to buying a 5.3 or 6.2. GM is really shitting the bed with the AFM. I had the trans case rebuilt at 8k, wheel bearing replaced at 45k, and injectors replaced at 58k. Since then its been a great pickup though.
I am currently looking at a 2021 or prior Tundra with a 5.7, F150 with a 5.0 or a GM with a 3.0.
The mileage is abysmal with the 5.7. The poor fuel mileage isn't so much related to motor design as it is the gear ratio. I wish they would have looked at changing the 4.3:1 gear ratio prior to replacing the 5.7 with a 3.4. I am not sure if the resale value vs the extra fuel costs pencils out at the end of the day with Toyota. The suspension leaves a lot to be desired. If you're strictly looking for a motor to last, this would probably be it.
Fords are ridiculously expensive for anything other than an XL with <40k miles. I think they have the best chassis. Very comfortable riding. Although it has evolved a bit, Ford has been putting 5.0/302 motors in half tons for quite a while.. If only they could come back with a revised 351W or 300 I6.
The 3.0 doesn't have a long enough track record to measure dependability. High 20s or low 30s mpg is attractive though. They should be run on the highway a bit, not really a grocery getter.. DPF/EGR/EPA is no friend of the motor in the long run. There are some quirks, mainly the oil pump belt. Engineers really knocked it out of the park with that one..
There is no good options, shopping for new(er) pickups sucks..