Every time my Windows gaming PC updates it nags me about setting up backups to OneDrive.
I cannot install Windows without a Microsoft account unless I apply work-arounds.
It constantly offers Office 365, even adding dummy icons to the start menu.
There are adverts on the login screen.
To be fair I installed Bazzite there, but for a laptop I cannot find an equivalent device at the same price point even ignoring the need for linux drivers.
Even after saying no to OneDrive and doing all I can to remove it, it tends to randomly come back months later and will automatically start uploading my desktop and documents folder to the cloud.
Edit: I even specifically bought the Pro version hoping to be able to shut some of this off.