Unfortunately it's an industry with a lot of stubborn old people so I don't see any major changes happening until they've retired but I'm willing to bet that async is going to revolutionize embedded development. Being able to await interrupts and doing efficient cooperative scheduling while writing straight forward code is a massive QoL improvement which is what embassy is enabling: https://embassy.dev/
Unfortunately Ada is held back by a genuine lack of awareness and some old misinformation baggage.
It's a good thing more people are realizing we really need to stop settling for C and C++, stop investing more money into tools that simply compensate for the weak foundation of those languages, and finally adopt safer alternatives.
People normally think that C is the best for low level embedded programing, but from my experience, it pales in comparison to the amount of low level control and type safety that Ada provides, even when you restrict yourself to a small subset of the language (note: Ada is often used on barebone systems and without an Ada runtime). Given the interoperability Ada has with C, it means you don't have to rewrite everything in order to incorporate it into existing code bases.
There are surelly other factors that weight in using C, but not for lack of options (in many cases).