A lot of new businesses are going the Notion/Google Drive route for docs, tables and knowledge, plus Canva for presentations and more visual work. It's not the majority, but the market is there.
The market may not yet be 365-sized but as GP mentioned: it's there.
And there are young people arriving at an age to open a business who have never used a Windows computer in their entire life. To them Microsoft is the company that make the virus-infested, slow, computers full of ads they see at their grandparents' house. That cohort ain't buying Windows / buying Office / using Azure.