thats why I suggested the idea of an RC low pass filter, the resistor will act as a current limiter, thats in case the microcontroller hasn't any current limit element connected to the PWM output, regarding the idea of 2nd or 3rd order LPF with a buffer, its good one but will add more complexity (circuit wise) to the system which I don't prefer, specially if you are an embedded systems specialist (which most of them don't like circuits that much) or still beginner in electronic circuits.
About the 100uf, it depends on the frequency, thus i don't think will be bad idea unless we know the PWM output frequency to calculate the Xc and then we can decide, actually such ideas aren't mine, they are commonly in many other designs, but thanks for clearing the image so anyone going to implement such idea and faced the overload issue he will be able to recognize and address the issue and move to the next solution.