Google Workspace or Microsoft 365 as the GTM primary stack in 2026, which won and why?

The default used to be clear. Enterprise went Microsoft. Startups and growth teams went Google.

That line seems less obvious now. I keep seeing fast-growing companies on Microsoft because an enterprise customer required it, and I keep seeing traditional enterprise holdouts experimenting with Google because of AI integration decisions.

For GTM teams specifically, not the whole company, the choice has downstream effects on every tool that connects to it.

Where has your team landed and what actually drove the decision? Was it a top-down company mandate, an integration requirement, an AI capability, or something else?