People don't realize that L.A. kids who were in HS anywhere like 04-09 were into Hyphy WAAAAY way way more than G-Funk. Mustard didn't even start producing until 2009, so of course his sound is more Hyphy influenced, yet...it still doesn't sound like Hyphy. They are really pointing out those Bass sounds he uses, and maybe the samples like "Burn rubber" and "This D," but his sound is way calmer and a bit slower than what Hyphy was.