Skype for Business (or whatever the legacy chat product is or has been called) dates back to 2007 and was typically present in your EA seat license bundle. Slack might be better than Skype, but it’s weird to suggest that getting into a market with an established history suddenly becomes anti-competitive only as soon as your competitor actually produces something that’s not a raging dumpster fire.
Skype For Business was a separate product. It's only when rolling it into the office suite that it becomes problematic. And that is only because of the dominant position Word/Excel/PPT hold.
I personally don't think it's anti-competitive but I at least see the argument that can be made.
it was. two years ago i changed job and the current employer use Skype for business as it was part of Office 365. we moved off Skype when Windows Team roll out.
