For blocking youtube ads on iOS (sorry don’t know enoug about iPadOS specifically) I am aware of a few approaches:
- Yattee is a youtube frontend, it is the equivalent to Newpipe (Android) on iOS. But it is much newer and much rougher around the edges, I would consider it not yet ready for general use but a good option to be aware of.
- Youtube in a web browser:
- Safari + Adguard (is what I use and recommend for iOS)
- Brave Browser
- Orion Browser (which has a built-in adblocker, but also allows you to use uBlock Origin)
With one very important caveat: Web Browser Adblocking on iOS works differently depending on whether you are viewing a page in the browser in the traditional way or if you ‘install’ a webapp (in iOS speak that is “add to homescreen”). Adblocking is less effective on iOS/Safari when you add a site to your homescreen to simulate the experience of a standalone app (which is probably what most people want in the context of youtube).
As others have already noted, DNS level adblocking isn’t capable of blocking youtube ads (or instagram, facebook, twitch). For these more pernicious ads. you need either a browser based adblocker or a 3rd party app or frontend.
There may be more options, but these are the options I am aware of.