As an embedded systems guy(Hardware guy who works "on"embedded firmware), i can attest to the fact that its not going anywhere, but caveat emptor, Its glacial growth when you consider career growth and salaries. Also, the tech stack is tied to a couple of big name tooling chain vendors and chip vendors. And after writing the same old I2C/SPI driver for the nth time, you start feeling like the OP. So grass is always greener on the other side.