I looked up "genius" because I vaguely recall its meaning has changed over eras. Found this - maybe it will help explain why "genius" struck you.

Today, the word genius tends to carry cerebral connotations, rather than spiritual ones, but the word has its origin in ancient Roman religion, in which the genius (from Latin gignere, “to beget”) was originally a spirit who gave continuity to a family or clan over generations, and later the attendant spirit of a person or place. When genius first made its home in the English language in the 14th century it carried this “attendant spirit” meaning. (Merriam-Webster)

That said, I agree heartily with your definition. "something that I am compelled

to shudder at, beyond greatness, something more akin to stunning and

so uncommon that the only valid response to it is to sit motionless, mouth

agape, and simply bathe silently in its wonder"