Overtime the requirements governing stairs have changed, mainly in the interest of improving the safety aspects of stairs. Therefore, older home have stairs and railings that that no longer conform to current standards, but still are very functional.
Most stairs and railings do not meet current codes
Home inspectors will often point out that the stairs or railings do not meet current standards. They do this so that the buyer is aware of changes and that if they choose, they can upgrade the stairs.
Desirable, codes and reality
Having stairs and handrails that are safe is certainly important. Over the years the codes have changed on what builders should do. Thus, many homes that are built prior to the current codes will have railings that do not meet the most current codes. People still use the old stairs and railings and most do not get injured. Reality is that there are millions of homes that have many things that are not to the current codes, yet people live in them safely and happily. Yes, it is desirable to have a home to the current codes, but basically the only way to accomplish this is to buy a newly built home.