I learned the abacus when I was a child. I thought it was silly, when I could do arithmetic much faster using pen and paper or in my head.
Also silly was that it was it was promoted at the time to be faster then a electronic computer or calculator. Which sorta was, if you ignore the fact you're comparing someone who can use the abacus quickly and that to a slow button pusher. And ignore actual computing time vs. usage time.
I hated learning the abacus, fortunately that didn't turn me away from math or my interest into computers, which happened much later.