Sadly that is true. It is also true that in engineering that can be dangerous. The first priority in mathematics is to actually know WHY 2+2=4. To accept a computation from a calculator or a super computer on face value is not a good thing.
Depends on the value of WHY doesn't it? ;-)
That was exactly the philosophy of an old college trig instructor of mine, John Saxon. He always felt that you should be able to forget everything about math in terms of formulas, etc., but should understand math theory well enough that you could re derive anything you might ever need to know whenever you needed to know it. He ended up writing mathematics textbooks using his unique methdology. My 10 year old is currently being taught by the Saxon method in her school (a private religious school).
So how effective is his method? Well, today, after several decades, I can still attack any project requiring math on any level with confidence that I can succeed. And, I rarely use math at all in my ordinary life.