The tangled affair now known as Watergate began 45 years ago, before most of today’s U.S. population had even been born. (The median age of Americans is about 38, so most people in the country were born in 1979 or thereafter.)
Thus for most people “Watergate” is a historical allusion—obviously negative in its implications, since it led to the only presidential resignation in American history, but probably hazy in its details.