I'm not sure that's what you're implying, but DNS-level blocking is not more powerful than filtering in the browser, at least in the sense of what it is capable of.

Content-filtering can and most definitely does block domains entirely, but it can also filter page elements served from the same domain which match a known ad "signature".

Though, if you can't run an adblocker, e.g. your Smart TV's browser then sure, DNS-level blocking is your best bet.