But compliance may be. For example, Slack charges a lot of money and requires a lot of users for actual HIPAA compliance (as in signing a BAA, everything else is marketing fluff). Teams, from what I can tell, comes with a BAA out of the box.
It's hard to deny Teams when it's already bundled with 365 that we're spending $25/user/month on, but if anyone has ever used both it becomes _immediately_ obvious that it's worth the money. That's the whole approach MS is going for, and something that's very very hard for Slack to combat.
The $12/user version does NOT include a signed BAA which means it is not HIPAA compliant for all intents and purposes. Like I said, anything without a BAA that says it's HIPAA is useless marketing fluff designed to confuse people. Only the Enterprise Grid product is eligible for a BAA and I believe even then there's some large minimum contract fee.