At least under the gdpr in europe it should be a privacy violation as you need to have the consent of the user to process it's data. So they would have to go to every single one in a comment and ask for permission if they want to use it for recommendations algos or check out if contents fits advertisement.
At least under the gdpr in europe it should be a privacy violation as you need to have the consent of the user to process it's data. So they would have to go to every single one in a comment and ask for permission if they want to use it for recommendations algos or check out if contents fits advertisement.