I think remembering is not the key to learning. Learning is understanding, in the sense mentioned in cloogschicer's comment + making connections with existing concepts: this is usually called "transfer". Transfer enables us to solve novel problems. Transfer is the real test, and probably the final goal, of learning.
I agree that there are many apps missing on Linux.
But that depends on the type of users: for devs & office workers, I think Google suite can replace MS Office and many Internet apps can help with many other types of everyday app that's available on Mac or Window.