I've never understood the "same type of receiver" thing

To me both Kupp and Woods are excellent WRs. And they're versatile- they can run short, intermediate, deep routes. Red zone. Great route runners overall. Block very well. Can run end-arounds. So, who cares then... I get that adding an OBJ or now Robinson is great because of what they can do. But anyway, to me WR similarity with CK and RW is irrelevant.