Not necessarily, our support team kinda loved it. I used the interfaces and it was pretty good software in many ways. They just didn't seem to be very capable when it came to medium complexity email setups. Many of their setup guides literally tell you to log into support address Gmail and set up a forwarding rule to send everything to Zendesk.
I suspect the issue is that we weren't paying enough. We had maybe 10 seats. I bet if you're buying 1000 seats a bunch of Zendesk engineers turn up and configure everything for you, but with the robust email setup needing that engineering time on their side to configure... so I guess in that way it may be Enterprise shitware.