The people you know worked long hours, but were they actually more productive?
Studies on working have consistently shown diminishing returns on longer and longer hours, generally past 30-40, depending on job type, i.e. physical jobs like assembly line work drop of slowly (mistakes rise but only gradually) vs intellectual jobs where mistakes either rise rapidly or people adjust by taking more slack time throughout the shift.
In all studies that I saw (and there is general lack of quality studies in that area - hard to set up realistic A/B experiment and observational data get you only so far) while average productivity dropped after 40h there were outliers (~10%) with no drop in productivity or increase in error rate with 60h/week. There is good chance that in elite job in Asia (and TSMC is definitely elite) almost everyone is in that category - can work very long hours without burning out. People who could not are either pushed out or leave on their own.
How long were those studies going on for? I can do 12-14 hour days for a week, I even once programmed quite challenging code for 36 hours without making anymore mistakes towards the end, but after I do this I'll be very tired for a few days once the rush is over.
Studies on working have consistently shown diminishing returns on longer and longer hours, generally past 30-40, depending on job type, i.e. physical jobs like assembly line work drop of slowly (mistakes rise but only gradually) vs intellectual jobs where mistakes either rise rapidly or people adjust by taking more slack time throughout the shift.