The article Lammy linked is indeed the correct one. When that bit of news came out I checked my account, and it turned out that Dropbox had added and enabled the toggle without my consent. I was a paying customer mind you, I paid like $120/yr for my storage. After they pulled that crap I started working on setting up Nextcloud hosted in a VPS. It's more expensive, but Dropbox permanently burned my trust when they did what they did.
> “For eligible accounts, […] The Third-party AI toggle is turned on”
I just logged in and checked and don't have the "Third-Party AI features" tab, but I only have an old free account and am probably not at the tier where this appears.
That feature doesn't train the model on customer's data though, unless I'm missing something.
I agree it's annoying it was enabled by default in places, but I'm trying to either correct the incorrect "for AI training" part, or find a citation that shows they are actually doing AI training with it.