An 8-bit microcontroller where memory is constrained and all the vendor libraries are written in C, is a good example.
Your 32-bit ARM M3/M4 cores are probably crossing that line where the memory cost of using C++ is worth it, but I would say there are still real world reasons to use C.
Though I would love to see more microcontroller vendors (or any) support C++ or Rust as part of they HAL libraries, but I think you will still find C to be perfectly viable for the low cost microcontroller application.
Your 32-bit ARM M3/M4 cores are probably crossing that line where the memory cost of using C++ is worth it, but I would say there are still real world reasons to use C.
Though I would love to see more microcontroller vendors (or any) support C++ or Rust as part of they HAL libraries, but I think you will still find C to be perfectly viable for the low cost microcontroller application.