Totally depends on where you live. Weather and culture matter. In areas that are already dense and maxed to capacity, biking is faster and easier and way less expensive. Will e-bikes replace trucks in mid-America, heck no. But I do believe they will supplant many commute vehicles in dense urban areas, in combination with public transit or on their own. I see it already in the Bay Area, where bikes are currently strong commute substitutes and e-bikes are becoming even more popular. In particular, retired folks here are buying up some pretty expensive e-bikes to ride around the Bay Area.