There are a couple of ways to block YT ads, but DNS-based adblockers won't do it.
On Android you can simply install an alternate YT client, boom, job's done. Works on Android TV also.
On iOS, the content blocker lists in Safari can block YT ads, but there's no way to block them in Google's YouTube app unless you jailbreak and install a modified app. So just watch YT in Safari.
You can side load YouTube tweaked apps. You’ll have to refresh the app every 7 days without a workaround or dev account but altserver makes it painless after the first time.
On Android you can simply install an alternate YT client, boom, job's done. Works on Android TV also.
On iOS, the content blocker lists in Safari can block YT ads, but there's no way to block them in Google's YouTube app unless you jailbreak and install a modified app. So just watch YT in Safari.