On pavement there is no traction gain needed with a fat tire. A 28mm tire will provide a softer ride than a 23mm but past that the benefits decrease and tire and rim weight increases substantially. Check out what is available from the tire manufacturers and the options for fat tires, i.e wider than 2.3" is very very small. Want a tire for pavement or one for dirt or one for gravel and the narrow tires provide many more choices.

Biggest problem I had with my two fat tire bikes was that I needed to modify my 1Up bike rack so the tires would fit on the platform and I needed to buy a motorcycle ramp to have one that was wide enough for the tires. I quickly sold these two bikes and replaced them with road e-bikes using 700x28c tires. Bikes were 27 lbs instead of 69 lbs and that made a considerable difference in many respects.