From my experience gym/steam/sauna is probably the only structured activity you have other than work, and probably "too weak vacation" if you are lucky. And those are just required to be physically functional. 5x12 in the office at PC/phone is absolute minimum, then one of the two weekends, usually Sunday, you catch up and prepare for the next week because during other days there is too much client work (in a general sense - both internal & external clients). So it gives you 72 hours minimum office/PC time, not average.

And then you are expected to be always online, even on rare vacations, and respond to emails very quickly. Plus work from remote desktop before bedtime and right after wake up to handle overnight emails and read news. So even if you are not in office you are constantly "ON" and the brain is always working, even on a treadmill in the gym... And then during IPO/initiation/reporting season it's actual 100-120 hours of actual office hours, but that are spikes, after which there is usually some relax time of only light 5x12 schedule. This is for research. Investment bankers in a narrow sense (IPOs, etc) just work in those spike/calm mode.

When I first saw the 996 story, my first reaction - given my background - was "whiner"... But in banking your monthly salary is just to cover your "costs of doing business" (but still high), only total annual compensation is a meaningful number, of which the fixed monthly part used to be less than half in good years. So in banking you kind of know why you are doing this. In programming bonuses are usually a much smaller fraction. Plus important thing - you could actually do 100 hours work if you do different work and are switching between tasks that load different parts of the brain. Financial modelling is comparable to programming (actually it is if we agree that Excel is the most used functional programming language) by cognitive load, but it takes a small share of total time. In the 996 case of constant coding it's very doubtful. I mostly do programming now and when I have 8 hours of uninterrupted clear mind spent on complex algos - that's a very productive lucky day. In the 6-8 hours range the focus and brain capacity usually drop so much that having good sleep & rest is much more important to have another good and deep 6-8 hours tomorrow.

But then you could write docs, add tests, do simple refactoring, setup backend & cloud, fight with configs - it takes hours and does not load brain as much as some concurrent lock-free data structure. Someone still needs to do that job and it could easily turn 6-8 hours into 10-14.