I need domain filtering: if the domain serves malware I want to block it, not just the known malware coming from it. If a domain serves porn, I want to block it on my kids computers (and mine) not just the content that is recognisable as porn. If a domain is used by malware I want to block it, and probably use the domain to determine the server, and block that too (too because the domain can move IP).
All of that can be implemented on the client (e.g. as a browser extension) without breaking the Internet. That's the only reliable way to do it anyway. MITM DNS filtering is easily bypassed and only effective against lazy malware.
