Stewart Butterfield says Microsoft sees Slack as existential threat

Main Idea: Stewart Butterfield said Microsoft sees Slack as an existential threat and argued that Slack still has a strong chance against the much larger company.

Key Points:

• Butterfield made the comments in a Wall Street Journal interview at the WSJ Tech Live event.
• He reacted strongly to a Microsoft chart comparing Teams and Slack user numbers during Slack’s quiet period.
• Butterfield said many large customers use Slack together with Office 365, not instead of it.
• He argued that smaller companies with strong customer traction can beat larger rivals, and he criticized Microsoft’s Teams tactics as leaning on market power.