Where did the stepney tyres found in earlier scooters go? Why did the companies stop using them?

With time, the technology of vehicles has also changed a lot. Today’s bikes and scooters are more efficient than the bikes and scooters of the olden days. If you remember, in the olden days, a stepney tyre was found at the back of the scooters, which was used in case of a puncture. This extra tyre was given so that if the scooter gets punctured on the way, the driver could replace it. But now this stepney tyre has been discontinued in the scooters. Let us know the reason for this.