Y'all, this is some 1990s ballmer stuff.
Like you want to make FoD a default? sure, fill your boots. But in cases where it was shut off, you don't know better. For example, in rural areas, internet access is slow, and if on satellite, metered. So you deciding to delete the local versions of stuff is going to cause folks to be in a sitch, because with satellite, once you hit your limit, you're shoved down to dial-up speeds until your monthly allotment is renewed.
Any of the onedrive engineers want to work with onedrive files at 57.6Kbps? Yeah, didn't think so. But that's what you're going to force people into, and that is not okay.
Contrary to what people who live in a gigabit bubble think, no, we don't all have perfect unlimited cell service, multiple gigabit providers, or a starbucks every three meters. There are a LOT of people in the US, and I'm sure outside of the US that this will, to be blunt, screw, and you literally didn't have to do this.
You don't actually know better than your customers about their internet connectivity. Maybe fix this?