The film that has most reminded me of 2001: A Space Odyssey
is The Tree of Life
(2011). It's not a science fiction film, of course, but they evoke very similar feelings about the place of mankind in the universe. They're also both films that feature visual effects supervised by Douglas Trumbull.
More directly to the point about the 1960s being a mythic period of experimentation in cinema, is there really another studio film from the era comparable to 2001: A Space Odyssey
? If not, as I think is the case, an outlier doesn't make for a strong argument that the past was superior to the present.