Earlier I had used the USB-C adapter to power my raspberry pi and an external PSU to power the servos. I had to connect the ground of the PSU to the ground of the R-PI so that the control signal from the R-PI is relative to the same ground as the servo.
Now I have my final PSU and am using it to power the R-PI over the 5V and GND PIN and not the USB-C input. The same PSU is also used to power the servos. Am I right, that I no longer need to artificially connect the PSU ground to the R-PI ground because ultimately it is already connected to the same ground as the servo?