Depends what you mean by "real". You may know this already, but the only difference between UDP and raw IP is the UDP header, consisting of 4 fields in 8 bytes: source port, destination port, length, and checksum. That's it; there's no other protocol overhead. Thus, from a pure technical perspective there would be basically no advantage to running QUIC directly over IP instead of over UDP. The only advantage is from a human perspective, that it's a little more elegant to put QUIC on the same layer as TCP.
In exchange... among other things, it would break all existing NAT implementations, since NAT is based on port numbers and existing devices wouldn't know where to find the port number in the new protocol. So everyone behind a home router would be unable to use the new protocol until they upgraded their router firmware – which of course most 'normal people' never do, so realistically you're waiting years until they get a new router.
Not only is that a gigantic practical disadvantage, it also feels rather inelegant itself. After all, routers shouldn't need to know the details of the transport protocol just to route packets. If it weren't for NAT they wouldn't have to, which is probably why port numbers aren't part of IP itself. NAT sucks. But NAT isn't going away; even on IPv6 some people insist on using it. By tunneling QUIC inside UDP, we at least regain the elegance of separating what routers need to know (IP + UDP) from the real "transport protocol" (QUIC).
In exchange... among other things, it would break all existing NAT implementations, since NAT is based on port numbers and existing devices wouldn't know where to find the port number in the new protocol. So everyone behind a home router would be unable to use the new protocol until they upgraded their router firmware – which of course most 'normal people' never do, so realistically you're waiting years until they get a new router.
Not only is that a gigantic practical disadvantage, it also feels rather inelegant itself. After all, routers shouldn't need to know the details of the transport protocol just to route packets. If it weren't for NAT they wouldn't have to, which is probably why port numbers aren't part of IP itself. NAT sucks. But NAT isn't going away; even on IPv6 some people insist on using it. By tunneling QUIC inside UDP, we at least regain the elegance of separating what routers need to know (IP + UDP) from the real "transport protocol" (QUIC).