I do not think it is due to unrealistic expectation. Unsatisfying is what driver companies like toyota having better products. The dissatisfaction comes from mismatch between ETA mpg and real mpg. There are two ways to gain fuel efficiency. One way is to use electric power for low power cruising, which toyota has adopted. The other way is to use that power to help acceleration. First only works when the driver is careful and the second is very robust with a bit lower EPA mpg numbers. As most other companies, toyota put short term financial interest ahead of consumer interest. If toyota has adopted the second design, EPA mpg would be lower, real mpg would be higher.

I live in the north, I would really love the second design and an EV switch.