I, and many others I know, are not saying our jobs are stress-free, but that overall we feel a lot less stressed now than we felt at Uni.Certainly, although you seem to equate enjoying your job with being stress free. I have enjoyed all of my jobs with several of them being very stressful.
You can disagree with the OP as much as you like, but it is a fact that many people do find Uni to be more stressful than the world of work. And yes, that includes people with very responsible jobs.
Therefore, the OP makes a very valid point and those who insist that it is always the case that the real world of work is more stressful than Uni , for everyone, are wrong, and that is what I am disagreeing with, very strongly.