Planet of the Apes was OK for SF of the time, which means it sucked. Taking a mediocre story, "hiding" a few civil-rights themes Hollywood-style, and putting some of the cast in bad Ape suits does not made good SF. I paid no attention to its sequels (which might be OK for all I know).

2001 came out in the same year and would hold its own today except for the lack of the three B's that audiences expect these days (Bullets, Bombs and Bimbos). And in terms of cinematic technique I don't expect to ever see anyone attempt anything like the first 30 minutes of 2001 again.

The only reason Apes got any love at all was that 2001 was simply beyond the comprehension of most Hollywood types.