This summary of what Jason says in the new video was posted at the other site...
ND is a 300+ person studio
-tlou2 has shipped.
-multiplayer game is in polish stage, bulk of team not necessary
-whatever their next big project is, it's in preproduction. A very small portion of their staff is concepting that next title.
-you have potentially 100+ employees(engineers, programmers, animators, etc) with not much to do day to day
-remaking an existing title with a highly anticipated HBo adaptation would be a relatively low scope, high profit project that the staff could be directed towards. They also get a chance to refine their tools, processes and become accustomed with the PS5 hardware so that by the time the next title is ready to enter full production, they're far more prepared.