Nice write up!

I've got a soroban but never got around to learning it. Definitely should pick that up again.

When I was at Uni (electrical engineering) I noticed that the Chinese students would reach for their calculator way less than western students and assumed that was because of the abacus.

Side note: they tried to shape a control theory subject (everyone was getting 100%) by disallowing calculators in tests. It was rough having to do things like long division for the first time in decades. Still everyone got 100% haha.