The answer, usually, is no. Wisdom is a quality that defies easy definition but psychologists who study aging have found that some of its components - judgment, emotional regulation - do improve with age in most people, consciously or not. Of course there is a subset of people out there who are sitting in their rocking chairs, spewing hate, but my guess is that these people weren't very pleasant to begin with, ... The reality is that the data are fairly convincing that people as they get older become more positive and less self-absorbed.