More often when I have seen Neutral busses in MCCs it’s because an inexperienced EE insisted on it “because it’s a 4 wire service”. I can’t count the number of times I have seen N-bus speced on an MCC for no good reason. Most of the time I can talk the EE out of it because it often makes the MCC special order, not because it’s difficult to add the bus, but it becomes problematic to add the terminations. The N will not have vertical bus bars in each section, so creating a way for a feeder breaker to be able to have a N-bus connection with proper wire bending space means it needs engineering input, which pushes the project into longer lead times.
If your MCC is existing and already has it though, I would probably run the N conductor to it. I wouldn’t want to explain to the future guy wanting to install a feeder for a 4 wire circuit why he can’t do it.
