[Matthias247]

Even without dynamic memory there's ton of useful things:

Namespaces, References, collection types (std::array, string_view, intrusive containers, etc.), RAII (release mutexes at scope ends), strong typing, proper encapsulation, interfaces, etc.

[Symmetry]

In general tools for constraining hardware complexity like namespaces and encapsulation are a lot less important for the project sizes where you're typically working with embedded systems. For the rest they mostly provide some benefit but that's offset by the danger of a move to a much, much larger and more complicated language in an environment where many people writing code are primarily EEs and most C++ answers they Google will provide solutions inappropriate for embedded development. And I say this as someone who was one of those EEs when he started out.