Where a circuit like this starts getting really useful is when you are using 2-wire BLDC/brushless motors (example 2-wire brushless cooling fans and blowers, being used for cooling systems in 3D printers).
True Servo Conversion for M.A.C.-R.A.C. “Sort-of-Servos” True servos read a control signal and move a motor or mechanical part as commanded. Some feedback is required to complete the control loop. The standard MAC-RAC runs a motor with two pushbuttons and uses their LED bar graph and the pilot’s sense of stick forces as feedback. True Spec Extreme Graphene 7.4V 4000mAh 87 Amps/120C LCG Shorty 5mm Inboard. Analog Output - Convert PWM to Voltage: Arduino's and other microcontrollers provide analog to digital (ADC) conversion to convert an input voltage to a digital value. You might think that they also provide the converse which is digital to analog (DAC) conversion. This is not the case. Tekin T-120 Speed 1/10th Scale Lo-Profile Onroad/Offroad Servo.
True Servo Conversion For M.a.c.r.a.c. Sort Sheet
In these brushless fans and motors, the two wires feed into a PCB built into the motor that controls how the motor is commutated (how the coils are energized in sequences to make the motor rotate). Advantage = quieter and longer lived motors and easy to power (you do not need to incorporate an ESC circuit, just power them up, and there are no brushes which can fail, generate dust, and be electrically noisy). Disadvantage: PWM mucks up how the commutator circuit in these brushless motors work (turning power ON & OFF affects the PCB/circuit).
True Servo Conversion For M.a.c.r.a.c. Sort C++
For brushless motors and fans, they are far better off when powered by continuous DC signals instead of PWM, and controlled by changing the voltage levels instead of using PWM signals.