Contact hours at most universities are around 2-4 hours per week per 15-credit module. To gain a degree, you have to take 120 credits a year, typically two terms of 4 x 15 credit modules, or 8-16 hours of contact per week maximum with the entire summer off.
You therefore have at least 24 hours a week to study on your own to bring your working week up to 40 hours. Maybe you're working, fair enough. But if you don't have time to study subjects in depth then you need to reduce your working hours. If you can't, then by definition you are not a full-time student.
This is not a personal attack on you. Perhaps you were genuinely studious and spent all your time poring over the coursework. It is a commentary on the whole academic sector where we repeatedly see students do nothing for most of the time and spend the last 2 weeks cramming and putting in substandard assessments, then blame the course material/their lecturers/their anxiety etc. for their poor results. And of course the leadership teams lap it up and tell us to make our courses easier.