Do not bundle! “Slack” is a communication/messaging app – now owned by Salesforce. Microsoft’s version of Slack is called “Teams”. Many companies use Microsoft Office (Word/Excel/Powerpoint) and Microsoft Outlook. To undercut Slack, Microsoft has included Teams “for free” in the price when companies buy Microsoft Office/Outlook. Even if Teams is a bit worse as a standalone product, it makes sense for teams already using Office/Outlook to just use Teams instead of pay for Slack.