Microsoft is introducing ads into a free version of Office, which seemingly only lets users save to OneDrive.
In other news, LibreOffice is also free, doesn't have ads, and lets you save your documents wherever you want. I use it every day for my work. It is available here:
Wall art in Oaxaca, Mexico.
(Edited to acknowledge the Mexican street artist, Yescka, thank you Mastodon. https://www.instagram.com/yescka_art?igsh=MzRlODBiNWFlZA==)