I noted in a previous post how I am somewhat 'old fashioned' when it comes to academic matters. That reminded me how, on various occasions, I have pointed out at my university department's staff meetings, when I did a course in education, one of the first things my cohort was told was that we were there to teach, NOT to be liked. Sometimes it takes a lot of effort on the part of the student to learn. It takes sweat certainly; tears sometimes (although, ideally no blood)*. That, I have been told is a thing of the past. It is now important that the students are kept happy. (This is because it is important to get a good score on the National Student Survey.)
Unfortunately, there are different types of happiness. There are students who are only happy if their teaching is thorough and challenging. They want it to require of them an effort. (As you can guess, these are my kind of students.) There are, however, students who want it all to be quite straightforward and set out for them in easy, non-taxing steps. (If not, woe betide, the lecturer.) I am not aware of any survey that makes a distinction between these different types of happiness - or student. If they did, institutions that deliberately cater for the latter would be seen as rather suspect. They would not be seen as at present, as successfully fulfilling students needs.
* That said, I do remember having to have blood samples taken in certain laboratory sessions. (Other fluid samples were also provided by other students.)