Their privacy policy says they don’t sell your data.

Not that you should automatically trust any communication platform (present Lemmies excluded), but exchange of data for services is at least not the business model on paper.

In a sense, you still “are the product”, because people won’t buy Nitro if there’s noone to talk to.

But that’s different from like… tracking micro-motions of your mouse to categorize your personality traits and increase ad conversions.