That overcompensating giant flat angry looking grill (I'm not being hyperbolic, that's literally why they style them that way: https://www.bloomberg.com/news/articles/2021-03-11/the-dange... ) and far too large/heavy body is why your truck has poor gas mileage, not because it has a "thirsty" V8.
2007 Toyota Highlander hybrid MPG: ~28mpg. Same vintage year prius mileage: a bit shy of twice that.
2nd gen Tundra weighs a LOT more than Highlander and has low final drive gearing for towing. The 4.7L and 5.7L V-8's are thirsty no matter the platform. Also, that model Tundra doesn't have a giant grill. Further, much of the weight in the Tundra comes from the giant components they bolt onto it to make it suitable for towing. For instance, a 2007 Tundra will pull 7000lbs more than a 2007 Highlander Hybrid.
I have no idea why you are comparing a small hybrid SUV to a full-size truck...of course the HYBRID suv is going to get more MPG.
2007 Toyota Highlander hybrid MPG: ~28mpg. Same vintage year prius mileage: a bit shy of twice that.