Huh what? IME, it's many MANY miles better in user experience than Cisco Webex and Skype for Business, these were absolute clusterfucks, unlike Zoom it doesn't do very weird hacks in the installer that led to security issues [1], and unlike Slack it has absolutely zero problems scaling to hundreds-of-users videocalls. Haven't experienced using landline telephony gateways with it yet, but I'll be glad to get rid of Cisco Jabber as well. Sorry to say it but Cisco's stuff is stuck many years in the past, their focus was on insanely expensive telephony systems and fancy conference room setups for too long. If there's one company that deserves disruption, it's them.
The point that competitors can rightfully complain about is the seamless integration with the rest of Office 365 products (create/provision Teams meetings from Outlook directly, and streaming Powerpoint presentations directly to clients as files instead of screengrabbing)... but hey, again, the UX is so much better.
[1] https://www.theguardian.com/technology/2022/aug/16/users-of-...