As explained already, loaders didn't pull back in GSX since 2012.
But since users asked for multiple services running at the same time, we HAD to move away the loaders momentarily, because now users CAN call Catering, Boarding and Refueling at the same time, so the rear Catering or the Fuel Tanker will surely clash into the Baggage Loader train.
Of course, this wouldn't have been necessary, if we just trust the user's common sense of not calling catering until the loader train finished, but then users asked for "automatic" servicing as well and, in this case moving away the loader was the only possible way to prevent this.
We might have a workaround, by moving them away only when the catering is approaching, but I cannot promise when this might be added.