The big giant hint with Astral is that there are zero meeting places, zero landmarks left by others, and zero skills resulting from it.
There are never any other humans there in all experiences I have had with it. It is just this vast nothingness distraction, and vast nowhere distraction, like some sick purgatory nonsense that has very little value except as a DISTRACTION to keep you from worthwhile practices.
When people make claims of astral meeting places, it is likely not the popularity cult version of astral nonsense that people claim happens to them.
Thus, it is not a place, or a realm, like we have in many dream practices. It is a trick. I have to add, in my humble opinion because of the petty tyrant people who think they have the right to censor and complain about OPINION pieces.
I feel that lucid dreaming and out of body experiences are far superior to the current astral popularity blah blah. And you can fluctuate between lucid dreaming and out of body experiences with some practice.
So, IMHO, astral is difficult because you are not gullible and are locked into real things with actual results.