It is true, the Catholic church is built on mysticism .. The saints, the monks, spiritual direction, meditation “dark night of the soul” ... all mysticism
You cam say it til the cows come home and it still won’t be true.
It is cherry-picking from the full spectrum of Catholicism.
I am not convinced.
Many Scriptures are also mysticism if we believe God enlightened minds of humans to write since God is a mystery and the Bible did not fall from the sky untouched by human hands.
You need to stop grouping Christian mysticism with non Christian mysticism