Did I see it or create it? A mysterious phrase: How could the swan know the joy of the swallow?

Ever since I was a child, I have loved dictionaries of proverbs and the like.
I spent my time reading them thoroughly from elementary school, and I even owned a pocket-sized one.

I have a memory of seeing a phrase written in that pocket-sized book.
However, there is a phrase that I cannot find in any literature I search today.

First, as a premise, I will present the 'original idiom'.

How could a swallow or sparrow know the ambition of a swan?

This is a phrase derived from a Chinese historical anecdote.

The meaning is that a small person cannot understand the ambitions of a great person.

Given the historical context, I understand the feelings of the person who uttered these words.
However, I have 'disliked' this phrase since I was a child.
This is because the arrogant mindset of thinking one is different from others shows through.

And here is the phrase I saw, or perhaps 'came up with'.

How could a swan know the joy of the swallow?

It is the antonym of the phrase above.

A great person cannot understand the joy of a small person.

For example, drinking alcohol.
Playing games while betting on a meal.

It is not permissible for a great person who cannot understand such 'joys' of a small person to take them away.

I suspect that is the meaning embedded in this phrase.

I realize myself that this is clearly over-spec for something an elementary school student would think of.
However, it is a phrase that has become my standard, and in fact, my tastes are closer to the way small people find joy.

What is the truth, really?
Even now, I still feel a sense of doubt.