SCTP is a flexible transport protocol with a crazy amount of features. It is message-oriented and each message on a connection belongs to a stream (of which there can be many). Each stream is optionally ordered, but this is managed independently for each stream in a connection. My understanding is that you can tune each stream separstely from unreliable, unordered to fully reliable and ordered as your application needs it.

This looks to me like a strict superset of what QUIC is intended to solve. And it is already supported in all major operating systems.