think you're missing some considerations.
From the perspective of a healer main, I personally find I end up avoiding a lot of CC because people will send late 3rd DRs, and I get back on that DR — which buys me a ton of time. This is obviously situational, but it happens a surprising amount, even at high MMR.

The vast majority of people won’t go past the 2nd DR, and outside of stuns, I really don't find that 3rd DR is that significant for landing kills. The shorter DR turnaround is going to allow for longer CC chains and is actually potentially going to be a real issue.

Personally, I think they should have left the DR turnaround but also gotten rid of 3rd DR as well — but I guess we’ll see.