The 750ti is a reasonable budget card
Unless he just didn't state it properly, he said he has the GTX750, which is not as good as the 750Ti.
So that would definitely be a limiting factor. But he still
might manage a reasonable 1080p/30fps/medium settings or so with it. It's not a super demanding game.
Also, the performance in The Evil Within can vary a bit with the level or the environment. Dont think the performance in Chapter 1 is going to be the same throughout the rest of the game.
Another thing to keep in mind is if you play with the aspect ratios through the console commands, it can have an effect on performance. If you're borderline, it could be the difference between drops below 30fps and a solid 30fps.
Lastly, they had a patch back in Dec 2014 or something that greatly improved performance on the PC version, so be wary of anybody who gives you impressions if they played it before that(where it had issues).
Really awesome game, though. Was my GOTY tied with Divinity Original Sin back in 2014. This is the game that Resident Evil 5 should have been. Like 5, this feels like something of an evolution on RE4, but The Evil Within is actually really good, unlike RE5.