"Not what it is cracked up to be" is a phrase used to express disappointment with something that did not meet expectations. There are several synonyms that can be used to convey the same sentiment. One such phrase is "overhyped," which indicates that something was overly promoted or advertised but did not live up to the publicity. Another synonym is "underwhelming," which suggests that the outcome fell short of one's expectations. "Disappointing" is another word that captures the sense of letdown or disillusionment that one may experience when something fails to meet expectations. These synonyms can be used interchangeably to describe situations or experiences that did not match the hype.