An Arduino board can output a generic PWM signal with analogWrite(), and also a signal for a Servo motor. I like to keep those two things apart, so I call it a "servo signal".
The Arduino Nano is for slow signals. There are faster Arduino boards, such as boards with a SAMD21G processor, for example the MKR Zero. Then there is more time to do calculations. Some will say that for a helicopter, the SAMD21G is still far to slow and a processor of a few hundred MegaHertz is needed, such as the Teensy 4.0.
The Arduino world is a different world than the remote control world. Reading a signal from a ESC and converting it to a digital value in a sketch and then making a signal for a Servo motor, that is not 100% accurate. If the code is not okay, then some jitter or hiccups might occur.
There are libraries to read a Servo signal from a ESC.
This one claims to be able to read a number of PPM channels: https://www.pjrc.com/teensy/td_libs_PulsePosition.html. Do you use PPM signals ?
Please give a link to the other forum.
I hope someone who knows all the terminology will reply.