Nah, Byford is 100% right (as usual) in saying this part of the plan is completely unnecessary.
As someone who uses Penn station every day, there are already a ton of infrastructure improvements in progress, and they will be plenty sufficient without demolishing block 780 (btw 30th & 31st Streets and 7th and 8th Ave). That block also holds the one remaining piece of the original Penn station and a beautiful and historic church, so it would be a real shame to demolish it.
Here’s another article that explains and shows renderings of some of the $1.5b in improvements that are already funded and approved.