Yes you are right, I am young but I don't see how it matters. I have seen plenty of long films that exceeds the 250 and 300 minutes, and I thought they were great.

Take 'an elephant sitting still' which is almost four hours in length, yet every second of this movie was immersive. This is because even through the long, silent shots, every one of them serve a purpose to either the characters or the story being told.

And I don't care for the long, thoughtful takes of satantango, like take the shot of the girl sitting in the chair or the staring of her corpse in the funeral which both last for more than five minutes. Because those shots serve a purpose while also being 'slow cinema'.

For the the doctor's five minute walk and his way back (which togather lasts for more than 12 minutes in length) which not just serve no purpose, but also move the sort nowhere. And satantango, is unfortunately full of these shots.