/diy/ - Do It Yourself

I'm currently working in a field that doesn't make me use microcontrollers directly, however when my contract will be over I would like to start going in that direction with my career. I don't have any official working experience with microcontrollers, but I have been working with them as a hobby for years, and recently I started really looking into being very proficient with STM32 micros and with the ESP32.
I know the STM is widely used in industry and control, whereas the esp32 is still kind of exotic and not vastly used even in the iot field, but I think the latter could be a better showcase of one capability with embedded software (rtos, dual core, more protocol/stacks to learn, etc..)

Considering however that I have a limited amount of time to dedicate to both, if I had to concentrate mainly on one type of micros, what do you guys think would be better in terms of employability?