Not necessarily. What happens on many coins, especially lesser Scrypt coins, and what KGW was designed to partially address, is that hash rate comes and goes very quickly as large multipools move their hash rate around. This causes very rapid changes in hash rate and block times until the difficulty adjusts. Adjusting too slowly can be as bad or worse than adjusting too quickly, because you can be stuck with extremely dysfunctional block times for a long period.

I don't really know whether it is true or not, but I've heard from some people who are not complete idiots that there was never a time warp exploit in KGW, and what as changed in AUR was window dressing serving as FUD repellant. And I'd add that ultimately didn't matter because all the "country coins" died anyway

As far as I know the only time wrap exploit that has ever been clearly identified and described is the original off-by-one bug identified by ArtForz in BTC and its clones.

I'm not ruling out that KGW might have an exploit or cryptonote difficulty adjustment might have an exploit, but big changes in hash rate or block times on AUR certainly don't demonstrate it at all.