You can already run Dioxus on an SBC. I’m not sure it’s realistic to run on an stm32 without some real limitations. IMO “everywhere” means everywhere in the physical sense, like desktop, mobile, server, AR/VR, handhelds, etc. we can’t support something like a Pic-8 ever, so it’s not worth trying to qualify that.
Given Qt, Slint[1] and similar, and Rust being supported on a lot of embedded platforms, it didn't seem out of place to imagine it on an higher-end STM32, ESP32 or similar.
I'm assuming there is a plan given "run anywhere".