That's what other players in the space do. I'd happily settle for C, in which case we wouldn't need to change the hardware much.
Serious question, do these run on stuff outside of “toy MCU’s” almost everytime I hear them mentioned it’s in the realm of education, hobbyist stuff, etc.
That's not my area of expertise, I was commenting on the hiring side. Maybe OP could use those "toy MCU's" as bait to attract some college interns? They might get lucky.
The Arduino portenta boards are pretty powerful. I just don't see where you would want to use one instead of a full OS