In terms of a teacher’s work load, marking is one thing but there are many more tasks that can stack up and collectively add hours to the working week.
In one of the primary schools I worked in we were all required to run an after school club which couldn’t finish before 4:15. We were also required to have 3 meetings a week (whole school, team and planning) and these often went on until 5pm. We were also required to evidence every lesson in children’s books so if they weren’t writing in books we had to take photos, cut and stick them in the books and photocopy each child’s white board work to stick in. We were also required to update the school’s social media account weekly and this was checked on and this is before we get to lesson planning, inputting and analysing data, parents evenings, phone calls to parents and being responsible for a subject (getting ready for Ofsted deep dives, maintaining a folder of planning across the school, delivering training in the subject, attending training, monitoring, maintaining and ordering resources for the subject, observing colleagues teaching the subject and feeding back, keeping a portfolio of the subject, skills analysis across the subject and book scrutinises in the subject across the school.) Not all schools focus on all these things or require them to be done in the same level of detail or time (e.g. fewer / shorter staff meetings, no teacher run clubs etc) so work load can vary enormously between schools and is so much more than the marking in books seen on parents’ evening.
I would never make assumptions about the workload in other jobs as you can’t ever fully know unless you are doing it. I’m also not saying the workload is heavier / harder than other jobs either nor am I moaning about it, merely explaining my experience of primary school.