Heinlein was a treasure for me back in the sixties (I was born in 1953)-- better than Asimov or Bradbury, and much better than Norton. It seems like a shame that modern people can't enjoy him as much as I did (it takes close reading-- something I didn't do when I was a kid) to notice some of the offensive bits, and that apparently now enjoying Heinlein tends to reflect badly (at least in some circles) on those who do.
However, there is absolutely nothing to be done about this, though I still recommend the better Heinlein juveniles.
And it's certainly true that there's so much more sf available now that older works are drifting into the past a lot faster. I think the tipping point was in the 80s-- before that, it was vaguely possible to keep up with new work while reading some of the older stories.