No the threat of the take down was always there in all his fights even when he used his wide karate style bladed stance. He has better TDD and defensive grappling than people realize. Not many will be able to ground him and keep him grounded while he's fresh. Took Khabib 2 rounds before he was able to ground him and get to work when he usually does it first takedown attempt. People look at Conor's grappling when he's tired and judge his grappling from those moments. His cardio/conditioning is the issue, his striking also looks bad when he's that tired and it isn't only his grappling that suffers.
Also the version of Conor that fought Dustin in the rematch is not the best version of Conor in terms of fighting style, sharpness, timing, speed, and movement. That version of Conor will lose more fights than he wins.