It has closed loop control, these [0] are a bit more proper serial servos with digital absolute magnetic encoders. Each one can be sent positional, velocity and even acceleration targets. I doubt anyone is looking for 0.2mm precision for $300 total. Or even 1mm precision.

The PAROL6 BOM doesn't provide any cost estimate, but it looks quite a bit more expensive.

[0] https://www.waveshare.com/wiki/ST3215_Servo