In the book, I don’t remember and think probably it’s just weird and subtle because part of the point of it is that it’s alien.
As I intend it here, yeah, it would be a distinct thing. I think almost everyone knows criticism can be painful to receive and rude to give, whereas advice can feel a lot more benign.
(I assume you are asking why it should be rarer, not why it is rarer.)
A few reasons, including:
It’s often given to children, where the best parenting book(s) caution against doing that too much (though of course there are tons of times it’s fine)
It’s often given to people in emotional distress, when it famously is less likely to work well
I suppose there may be lots of cases where upregulating advice would be good, and that these outweigh the common cases where downregulating it would be good. I just haven’t thought of those. If you have, I’d be interested in hearing them!