Honestly the Segway had a couple of useful effects, none of which involved the Segway itself becoming useful or popular. 1. The self-balancing tech spread to a

Honestly the Segway had a couple of useful effects, none of which involved the Segway itself becoming useful or popular. 1. The self-balancing tech spread to a variety of more interesting and cheaper "toy" platforms like hoverboards and self-balancing electric unicycles. 2. They encouraged the interest in electric micromobility, leading to, especially, electric scooters (which are simpler, cheaper, and use less space) becoming widespread. This is kind of like the point someone else made that the actual useful thing the blockchain craze produced was "cleaning up your database schemas with the idea of putting them on the blockchain, then never putting them on the blockchain".