https://twitter.com/cgyrling/statuses/484003562351886336

https://twitter.com/Neil_Druckmann/status/489492701482848257

https://twitter.com/Corrinne/status/489418484212711424

https://twitter.com/Corrinne/status/489416608205385729

Multiple Naughty Dog devs have explicitly confirmed it runs at a solid 60 fps. Which means almost no drops from 60. Is it really that hard to believe a PS3 game could run on PS4 at 1080p 60 fps?

No that isn’t what Digital Foundry said, this is a quote directly from the article: http://www.eurogamer.net/articles/2014-07-16-the-last-of-us-remastered-lets-you-lock-frame-rate-at-30fps

“By default the game runs at 1080p60 in single-player and multiplayer,
but the addition of the 30fps lock MAY indicate occasional drops below
60. If you are locked at 60 you get no judder. If you aren’t, you do get
judder (or tearing), and so locking to 30 produces a more consistent
experience (for more on this subject, check out Digital Foundry’s
article “Do higher frame-rates always mean better gameplay?”).”

So the key work in their article is MAY.

This isn’t a comment made after their performance text was complete, it’s speculation on why Naughty Dog has included the option.

It’s possible there are dips, but from Naughty Dogs own past comments they were shooting for higher than 60FPS to make sure the game stays locked at 60 at all times.
In fact 60FPS is one of the main things at least one of the developers found to be a revelation.

It’s equally possible that 30FPS is included because some gamers may prefer 30.
We’ll find out when DF does their test for sure if the game stays locked or not.

Meanwhile, PC gamers shrug and ask, “Where’s 2160p120fps?”