Being able to access parts of buildings, whether they be public or private, is not always as easy for people with disabilities, the old or infirm, those with debilitating illnesses or those that have recently suffered accidents that have either temporarily or permanently left then unable to get around as easily as healthy, able bodied people can do.
For this reason, there needs to be devices, equipment or ramps to facilitate easy access for those who need it. Now, that's not always possible or feasible in private houses and we understand that. But certainly in public buildings there should always be the facilities for accessing the parts of those building that are open to the general public or to employees working in the building who have these certain disabilities which may otherwise preclude them from access.
The vast majority of public building have upgraded their access points to include elevators, stair lifts, handicap ramps and other similar means of access to upper floors or raised areas. These buildings also provide handicap bathroom facilities which of course are generally standard in all public buildings. Things have certainly improved from the way they were thirty years ago and they continue to improve as better, easier to use and more reliable accessibility equipment is developed.