Example: Old people often complain about young people not having "basic knowledge" and say that younger generations know and understand less of the world than they do.
It's entirely subjective and one generation's "basic knowledge" may be someone else's "useless esoterica."
For instance, old people jerk themselves a lot about writing cursive and driving stickshift (and winning WW2 somehow???) but don't know how to put their phones on silent.
On the other hand, people are forgetting how to read and how to learn, and I'd say that's basic knowledge... so, case-by-case.