What makes it uneasy is not only upscaling but they are generating new frames to make it 60fps. 60fps by itself feels fake (check some footage of The Hobbit that tried 48fps). It feels like video games.
It's kinda funny to aim for 60fps because modern video productions will often have 60fps footage that's too sharp and clean. So they heavily post process the videos. You add the film grain and lower the fps to 30 or even 24 (cinema) so it looks much more natural.
The question is if this is just habitual / taste thing. We most likely wouldn't prefer 24fps if the movie industry started with 50fps.