Eh, i see the difficult label as a matter of perspective. Sure they are a little less hardy then most and a little more care should be taken. But after keeping them i'd in no way label them as difficult, or difficult enough that a avid fishkeeper can't keep.
For a beginner, ehhh yeah maybe could pose a challenge. For someone keeping fish for a short while, shouldn't be much of a problem. Just keep up on the water changes and provide a decent diet and thats it.
I find Blue Rams to be more difficult to keep then discus....i just can't keep rams alive in my tanks but my discus used to thrive (got rid of them just recently).
And to that last sentance, yes the view has changed for the most part. More is known about them now. The amount of breeding taking place now is huge steps above what it used to be also.