I'll tell u why.
Because Funk Master Flex who saw the 70's once spoke about how 70's cats was looking at 90's cats as not doing hip hop like how it originally started. But aint no one gonna tell a 90's cat what they were experiencing wasn't real hip hop. Same rule applies to this generation.
The problem with this logic is we've had 20+ years since the 90's to judge it objectively, completely independent of how people (including those 70's cats) originally perceived it. And most people, objectively speaking, would agree 90's hip-hop was an improvement over 70's hip-hop. Including people that were doing it before the 90's.
Fred.