Reminds me a lot of the Tactical Microgrid Standard (aka TMS aka MIL-STD-3071) [1], probably just because TMS uses DDS as well. I would really like to know if there is a protocol that functions like DDS but caters to real-time guarantees and prioritizes (at a "simple protocol" level) usability on embedded systems with no dynamic memory allocation. It would also need to be just-as-functional with non-real-time systems. One problem with DDS is that it is too heavy-handed to implement well on an embedded system.
Pretty sure there are DDS implementations that provide most of that, maybe with memory pools instead of no-allocations.
Other than that, PX4 uses an in-memory only pub/sub for internal data bus, somewhat inspired by DDS