On his awakening Buddha's compassion to teach was extended to saintly people who he saw as taintless and could understand his teaching not to everyone. Even in Buddha time the higher teaches was exclusively to the monks who have gone forth.
Quoted below is Ven. Sariputta telling the Anathapindika the householder in his death bed that the teaching on detachment is not given to lay people clad in white.
A learner with undeveloped virtue may or most likely will misunderstand the higher teaching and could loss his / her innate goodness. So there is real danger teaching to everyone the higher teaching of non-self, impermanence alike.
I dare say, website like this and many websites which elaborate and allow unbound discussion on the higher teaching of Buddhism is off-putting to most teachers, and most likely will not get approval had it been present in Buddha time. Website like this are probably doing more damage than good to many.
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"Then, householder, you should train yourself in this way: 'I won't
cling to form... feeling... perception... thought-fabrications; my
consciousness will not be dependent on thought-fabrications.' ... 'I
won't cling to consciousness; my consciousness will not be dependent
on consciousness.' That's how you should train yourself.
"Then, householder, you should train yourself in this way: 'I won't
cling to the dimension of the infinitude of space... the dimension of
the infinitude of consciousness... the dimension of nothingness; my
consciousness will not be dependent on the dimension of nothingness.'
... 'I won't cling to the sphere of neither perception nor
non-perception; my consciousness will not be dependent on the sphere
of neither perception nor non-perception.' That's how you should train
yourself.
"Then, householder, you should train yourself in this way: 'I won't
cling to this world; my consciousness will not be dependent on this
world... I won't cling to the world beyond; my consciousness will not
be dependent on the world beyond.' That's how you should train
yourself.
"Then, householder, you should train yourself in this way: 'I won't
cling to what is seen, heard, sensed, cognized, attained, sought
after, pondered by the intellect; my consciousness will not be
dependent on that.' That's how you should train yourself."
**When this was said, Anathapindika the householder wept and shed tears.
Ven. Ananda said to him, "Are you sinking, householder? Are you
foundering?"
"No, venerable sir. I'm not sinking, nor am I foundering. It's just
that for a long time I have attended to the Teacher, and to the monks
who inspire my heart, but never before have I heard a talk on the
Dhamma like this."
"This sort of talk on the Dhamma, householder, is not given to lay
people clad in white. This sort of talk on the Dhamma is given to
those gone forth."
"In that case, Ven. Sariputta, please let this sort of talk on the
Dhamma be given to lay people clad in white. There are clansmen with
little dust in their eyes who are wasting away through not hearing
[this] Dhamma. There will be those who will understand it."
Then Ven. Sariputta and Ven. Ananda, having given this instruction to
Anathapindika the householder, got up from their seats and left. Then,
not long after they left, Anathapindika the householder died and
reappeared in the Tusita heaven. Then Anathapindika the deva's son, in
the far extreme of the night, his extreme radiance lighting up the
entirety of Jeta's Grove, went to the Blessed One and, on arrival,
bowed down to him and stood to one side.
https://www.dhammatalks.org/suttas/MN/MN143.html