OP mentioned having ADP and automatic backups enabled and I believe iCloud sync uploads photos continuously. The biggest risk is as you say battery saving and if it will upload data over mobile data (should be a setting for that).

Further than that I would say the big question is if someone else would actually be able to access the data if OP is detained… and of course https://xkcd.com/538/ (I don’t think the random chuds in ICE would have the know how for any technical bypass)

I have heard a lot of people complaining about deleting the Local copy… It seems to mainly be a bad faith argument where deleting the Local copy just refers to the process of freeing up local storage of unused files(?) repeated by people who doesn’t actually use OneDrive but want a unarguable point to why it’s shit.

(Mind you I think it’s bad enough that Microsoft tries to kind of coerce you into handing them your data)