Okay, okay, so the whole thing about driving DC motors at low speed. Surely, the brushes limit the lowest speed you can reliably drive such motors at? So, brushless DC motors could be driven at lower speeds, could they? Well, looks like they can. However, they do so at the expense of less torque than stepper motors. So, what it comes down to is that stepper motors are the most effective way to get very small movement from a motor, but if you want to cut costs, yeah you can use a brushless DC motor or a brushed DC motor with a gear reduction box.
So, the critical question is how much cost can you cut before your compromise on accuracy is too great to be usable for your application? Only you can answer this question for your specific application.
20191122/DuckDuckGo low speed brushless dc motor
20191122/https://www.quora.com/Why-cant-we-use-a-BLDC-motor-for-low-speed-applications?share=1
20191122/https://www.amazon.com/Makermotor-Variable-Brushless-Electric-Gearmotor/dp/B005LY2LDO
20191122/https://hackaday.com/2015/04/20/driving-a-brushless-dc-motor-sloooooooowly/