What "looks" better is SUBJECTIVE. For a keen eye one can decipher the intricacies of the film format on screen... which some digital folks are trying to replicate digitally.
It's all NOSTALGIA. People are accustomed to that 35mm film look & that's what they expect. A lot of people were raised & grew up watching 35mm like Tarintino. Some folks made their early movies on film (Tarintino, Speilberg).
It's just a PERSONAL PREFERENCE. "Better"? Digital has many MANY ADVANTAGES over film that can't be argued, period. Cheaper, easier, proficient, MUCH Quicker, ect ect. But the LOOK of the final print (which is still crazy since most people are xfering the film to DIGITAL to EDIT, but I guess they're talking SOURCE of the picture.
BTW, 35mm film IS equivalent to 4k,.. or, ACTUALLY, rather closer to 5k. they tested it & it's been a fact since the advent of digital in the 90s.
(I HATE how misleading the "k" numbers are.. 1080 & lower it's the number of digital lines up and down. then all the suddenly from 2k on up, they count it in lines ACROSS. It's stupid.)
RED engineers & others will continue to develop digital cameras & they will create a sensor and capturing recorder that can record 70mm equivalent one day, but even digitally, that is just not practical at this time - they're going good just to record 4k.
And then there's the practicality of filming in & final print in 4k. Most theaters show "2k" images anyway! 4k is only future-proofing to go back one day & re-master it. Online isn't 4k compatible just yet (there's been articles proving this). Digital is getting there, and i LOVE it, but it's not quite "there" (100% "better" than film yet.) But As Peter Jackson proved with Hobbit, digital CAN be beautiful.. so much so, it makes audiences uncomfortable seeing THAT pristine of a image. Which is a complaint I think it ridiculous,.. but alas, people are USED to the old film look... nostalgia not perfect quality. Kinda sad in a way. I'd think cinema's SHOULD strive to be pristine beautiful picture,... not some nostalgia BS. Progress is good... IMNSHO