Disappointing yes, surprising no. This route and in particular the stop at Sheffield and passenger take up there has been a nightmare for far too long.
I travel this service often, generally Nottingham to Sheffield / Chinley and occasionally to Manchester and there is no sign at all of anything improving. Another classic for this nonsense is Leeds - Nottingham which whenever I have been on it recently is a horrendously overcrowded 2 cars, that is if it is not cancelled - admittedly not an EMR service but there does seem to be something about Sheffield and EMR / Northern services that creates a bit of a bit of a bottleneck for these types of problems.
As a general comment about my experiences of EMR in the last few months, it has been poor. From trains that start the journey filthy and bins overflowing, no catering when the service is planned to be ran with catering, no announcements, cancellations, delays, staff shortages because covid, seat reservations "not working", short forms and overcrowding, overcrowding, overcrowding. I can maybe forgive some of this but most of it seems to be systemic and some of it is just really basic stuff going wrong. My feeling is that they have so many issues that are deemed to be insurmountable that they have just stopped caring.