This thread is basically dead right now but I've only just found it and I can't resist a 'make if list of films to fit category X' challenge. Sorry!
I can't stress enough my experience that today's younger film fans agree that anything before 2000 is the olden days and might only be watched under duress. So the original question is proper valid - what are the new all-time classics?
Based on compulsive listening to the Empire podcast, there are clear examples out there, and indeed fimmakers who are just as loved as Scorsese, Spielberg, Coppola etc were in their day (and of course they do still make movies)
Any new film by C. Nolan or PT Anderson or G. del Toro or the Coens is going to be greeted with reverence, and there's by now two generations of people raised on Pixar movies who will quote them forever (not to mention a hefty chunk of Disney - Frozen and Moana are cultural juggernauts, and decent films as well, as if that matters). And yes, Harry Potter and Marvel are inescapable touchstones of conversation...
Pretty sure there's a very healthy Horror canon right now, centred around Insidious/the Conjuring, but I think for decades teens at sleepovers will be daring each other to watch The Babadook, It Follows and Hereditary, and dare I say it, It. (and from the 2000s there's enduring love for: 28 Days later..., the Descent, Wolf Creek and Cabin in the Woods).
Hard to name a bigger cultural hit than Get Out, too (even if it's kinda like a very good episode of Black Mirror - as peple have said before, it's TV lately that seems to be the go-to for intelligence rather than spectacle)
Other films since 2000 that I believe people who haven't even watched them have heard of and can maybe quote from, or at least know what it's about (sorry if I'm repeating suggestions from upthread):
Eternal Sunshine; Lost in Translation; Brokeback Mountain; Before Sunset/Midnight; the Fast and bloody Furious franchise; Mamma Mia; The Greatest Showman; Whiplash; Moonlight; Call me by your Name
Most of those are even quite good! I guess they're less concerned with 'brooding exploration of masculinity' than the original exmaples listed in the thread?
Sure, there are more films (and TV) being made than ever, and more platforms to watch them on - but I still think there's as much shared cultural conversation going on about a relatively small number as there always was...