The classic example is wheel chair ramps. Who benefits from those? People who have bad knees, people with strollers, people with heavy roller bags. The ramp was installed for wheelchairs but everybody benefits. If the solution were limited only to wheelchairs almost nobody would use it. It would just be in the way and be more of a problem than a solution.
If you are only solving for blindness you don’t really understand accessibility and are just in the way.