Interop can be useful, but who gets to collect all the data when you hoopkup e.g. WhatsApp and Telegram? Both, I'd imagine. How would you remove data/opt out of

Interop can be useful, but who gets to collect all the data when you hoopkup e.g. WhatsApp and Telegram? Both, I'd imagine. How would you remove data/opt out of a platform you never accessed before? There's a lot of leeway there.