That would be true if you could fly any of those turns in 9 hours. There will be a few in the Caribbean that can be flown in 8:30. Probably only 2 or 3 max perhaps less. The company is using a 30 minute buffer. In JFK as a example there is a turn next month at 8:57. It is however doubled crewed to avoid the new hard time restriction.
On the domestic side there will be no turns. I am amazed at how often this keeps getting posted by experienced pilots. Simply go look at the block times from any East coast destination to the west coast.
JFK-LAX is just under 12 hours
JFK-SFO is over 12 hours
JFK-SLC over 10 hours
ATL-LAX is over 9 hours

There will not be any East Coast to West Coast turns. 9 hours does not allow for it. There might be some turns from DTW however even then I suspect you wont see it often. When you build trips if you pull the long legs out for turns it becomes very difficult to build the rest of the trips without increasing credit time. You could as a example build a ATL to Vegas turn. Its just a minute or two under 8:30. If you take those legs out of the trip mix for turns you more then likely see a increase in credit on other trips. You also run the risk of the crew going 32 minutes over on the first leg and having to cancel the 2nd leg. The whole oh my god we will be flying giant turns is much ado about nothing!
Even if they could fly all those cities as turns it has no effect on manning. Again this seems to be a urban legend. If you fly a 4 day trip doing transcon there is normally no credit in the trip. It takes the exact same number of pilots to fly it as a 4 day or as 2 turns. Manning is very simply. Block hours plus credit hours equals manning. Turns will have no impact on the block hour number and the long legged trips generally have no credit hence no change in manning.