I think the problem is less that they don’t teach hashkafa and more that they preach intolerance.
If they would teach a variety of opinions, but with an attitude of “there are lots of opinions precisely because there’s no one path you are obligated to follow,” that would probably confuse people less. Of course, the people preaching intolerance would likely disagree with that statement as a matter of fact. But I’m not arguing that it’s true; I’m pointing out that it’s the cause of a problem. When they analyze the opinions as if they are opinions in halacha, as if one matters more than others, it can be quite stressful, especially when the teachers are not not competent enough to conclusively demonstrate why.
Equally stressful to a student is when a school preaches intolerance of other hashkafos but never bothers to formally outline and substantiate its own.