Plenty of embedded microcontrollers in the 70s and later not only used floating point but used BASIC interpreters where math was floating point by default. Not all commercial embedded applications are avionics and ECUs. A lot of them are more like TV remote controls, fish finders, vending machines, inkjet printers, etc.
I agree that fixed point is great and that floating point has portability problems and adds subtle correctness concerns.
A lot of early (60s and 70s) embedded control was done with programmable calculators, incidentally, because the 8048 didn't ship until 01977: https://www.eejournal.com/article/a-history-of-early-microco... and so for a while using something like an HP9825 seemed like a reasonable idea for some applications. Which of course meant all your math was decimal floating point.
No, though chips like the 80186 did blur the line. But what I mean is that different companies sold things like 8051s with BASIC in ROM. Parallax had a very popular product in this category based on a PIC, you've probably heard of it: the BASIC Stamp.
I agree that fixed point is great and that floating point has portability problems and adds subtle correctness concerns.
A lot of early (60s and 70s) embedded control was done with programmable calculators, incidentally, because the 8048 didn't ship until 01977: https://www.eejournal.com/article/a-history-of-early-microco... and so for a while using something like an HP9825 seemed like a reasonable idea for some applications. Which of course meant all your math was decimal floating point.