A possible hint to the answer comes from the Buddha in MN26:
"Then the thought occurred to me, 'This Dhamma that I have attained is
deep, hard to see, hard to realize, peaceful, refined, beyond the
scope of conjecture, subtle, to-be-experienced by the wise. But
this generation delights in attachment, is excited by attachment,
enjoys attachment. For a generation delighting in attachment, excited
by attachment, enjoying attachment, this/that conditionality &
dependent co-arising are hard to see. This state, too, is hard to see:
the resolution of all fabrications, the relinquishment of all
acquisitions, the ending of craving; dispassion; cessation; Unbinding.
And if I were to teach the Dhamma and others would not understand me,
that would be tiresome for me, troublesome for me.'
Almost all sentient beings are here because they want to be here and they thoroughly enjoy attachment, eventhough none of it is permanent and none of it is permanently satisfactory. Even if they suffer much (for e.g. in hell), they continue to cling to their selfhood and maintain their craving to-be, not ready to let go.
If you look deep into yourself and find that you're not ready to let go of your selfhood and not ready to let go of your craving to-be, then you could empathize that this is indeed the case for the googolplex of beings out there.
Even if you had the power to end all sufferings, I bet there would be great opposition to that, from the vast majority of beings who are not yet ready to let go.
MN75 provides a reason why sentient beings see "painful" sensual pleasures with a biased perception of being "pleasant":
"Now suppose that there was a leper covered with sores & infections,
devoured by worms, picking the scabs off the openings of his wounds
with his nails, cauterizing his body over a pit of glowing embers. The
more he cauterized his body over the pit of glowing embers, the more
disgusting, foul-smelling, & putrid the openings of his wounds would
become, and yet he would feel a modicum of enjoyment & satisfaction
because of the itchiness of his wounds. In the same way, beings not
free from passion for sensual pleasures — devoured by sensual craving,
burning with sensual fever — indulge in sensual pleasures. The more
they indulge in sensual pleasures, the more their sensual craving
increases and the more they burn with sensual fever, and yet they feel
a modicum of enjoyment & satisfaction dependent on the five strings of
sensuality.
For the multitude of sentient beings who want to-be, the best thing that you can wish for them, comes from the Karaniya Metta Sutta:
Think: Happy, at rest,
may all beings be happy at heart.
Whatever beings there may be,
weak or strong,
without exception,
long, large,
middling, short,
subtle, blatant,
seen & unseen,
near & far,
born & seeking birth:
May all beings be happy at heart.