How can maximum number of minimum cuts of a graph be exactly $n \choose 2$?
"Maximum" here means that no graph can have more than $n \choose 2$ minimum cuts. Obviously, you can come up with graphs (or infinite families of graphs) that have fewer minimum cuts, like say $n-1$. This is less than $n \choose 2$ which is perfectly fine, so this is no contradiction. In other words, the result only means that you can't come up with graphs that have more than the maximum number of minimum cuts.