As for your concern that rooting and using advanced DNS/hosts/firewall blocker aim to block ads but not improve privacy, it is already hard to maintain privacy when you opt into proprietary streaming services like netflix or hbo, as in the post Privacy-respecting and legal alternatives to streaming services. These streaming services have to collect the data of what you watched in order to pay the creator, and they will definitely share this data with marketing to analyze what type of content you like to watch and use it for “personal recommendation”
Blocking privacy-invasive or anti-consumer ads is the next best option for privacy. Especially on annoying services, such as the rumored “8 minutes unskippable ads on paramount” (lol)