I don't think Segways were ever really intended to compete with bicycles. People make that comparison alot, but it's really not valid.
A closer comparison is a scooter or moped type of device. Those will fit through some doorways, but being gas-powered they are generally excluded from use or storage in most indoor areas. Cost is comparable, although the scooter would win out on distance and top speed. Most scooters are also too heavy for a single operator to pick up and move, and they also don't generally break down to fit easily in the trunk of a vehicle.
Segway's, even the non off-road models do quite well on dirt/trails, so that isn't an advantage for the bike. They could go in the streets as well, the only limitation there is erratic legislation, so it's hard to make a direct comparison.
A closer comparison is a scooter or moped type of device. Those will fit through some doorways, but being gas-powered they are generally excluded from use or storage in most indoor areas. Cost is comparable, although the scooter would win out on distance and top speed. Most scooters are also too heavy for a single operator to pick up and move, and they also don't generally break down to fit easily in the trunk of a vehicle.
Segway's, even the non off-road models do quite well on dirt/trails, so that isn't an advantage for the bike. They could go in the streets as well, the only limitation there is erratic legislation, so it's hard to make a direct comparison.