The thing is, whether one was a big fan of his work or thought he was slight, that's beside the point. He wrote three Broadway musicals that were massive hits. (The first-ever to write three musicals that each ran over 1,500 performances.) Two of them were significant. One was critically important to popular culture. In fact, its title song knocked The Beatles out of #1 on the charts.
The three were Hello, Dolly! that ran for 2,844 performances (that's around seven years), which at the time made it the longest-running musical in Broadway history. Mame had 1,508 performances, and La Cage aux Folles ran for 1,761 performances. He also had a big hit with his first book musical, Milk & Honey. In addition, the Broadway revue Jerry's Girls with his songs had a successful run, and he wrote the enjoyable score to the CBS movie, Mrs. Santa Claus, as well as several other Broadway shows, none which were successful, though most had very nice scores. He won two Tony Awards and received a Lifetime Achievement Tony.
This begins with Kelsey Grammar who starred in the revival of La Cage aux Folles.
And here's about 25 minutes from a wonderful tribute to Jerry Herman at the Hollywood Bowl in 1993, which ends with a rousing performance by Herman himself at the piano singing his song, "The Best of Times" from La Cage aux Folles, joined by the entire cast.