Most companies who have your personal data also respect the privacy of your data or at least they follow the terms and conditions you agreed to. The problem is that no-one reads those terms.
Who would want to read that long sentences and paragraphs? we're on the days that we just want to sign up and we don't really care that our data were stored and they can use it freely depending on their choice. But yes, I agree that still most of them are following the terms of use of keeping our data privately.
And maybe I will only believe in big platforms like whatsapp, facebook, google because I believe this platform will not violate the privacy requirements of users. But unlike the platform that I just knew or new, they usually steal user data and sell it on darkweb.
Noway companies are going to accept this and unfortunately we cannot prevent that such giants as Facebook and Google are just stealing our personal information and selling it for huge amount of money. This is their major business.
Easy, you just don't use it, your data will be safe. Facebook and Google actually never sell user data they only use your habits as a business ad on their platform, here users, Facebook and advertisers both benefit and your data remains safe.