Yes you can do that in iOS 13 but very few people are tech savvy to know that. With iOS 14, the dialog would be in front of you as you the app. High chance everyone would opt out

Do you watch youtube? thanks for supporting the creators with ads?

Please iPhone may be private but if you use Google search you lost already.

It is a double-whammy. You pay lot to apple and then lost privacy to google/netflix/cnn/<app> here or whomever.