Even if I had a dumb TV, and a secure trustworthy streaming box, the services themselves(Netflix et al) are collecting the same data, no?
Collecting, yes, but not selling. ONN explicitly says they do so in their privacy policy.
https://onntvsupport.com/privacy-policy
>We may disclose “blinded” aggregated data and user statistics to prospective partners and other third parties. Blinded data is data that does not identify an individual person.
Netflix says - https://help.netflix.com/legal/privacy
We may share information collected from or about you with Advertisers and/or Ad Measurement Companies to select advertisements, and measure and improve advertising effectiveness. As a reminder, please see the Information from Other Sources section above if you have questions regarding the role of Advertisers or Ad Measurement Companies.
Hulu says - https://press.hulu.com/privacy-policy
We may share information collected from or about you with third parties as explained further below, including business partners, social networking services, service providers, advertisers, and other companies that are not affiliated with Hulu.