I think there's a really big difference between legit staying up, as in not even laying down to rest for 48 hours and laying in bed with your eyes mostly closed for 6-8 hours at night while consciously knowing you're not sleeping.
Human bodies react very differently too.
I remember doing a tech related trip once where it was crazy schedules (up at ~6-7am and back in the hotel room at 9:30pm-10pm) for 3 nights and then waking up at 4:45am on the last day to catch a 6+ hour flight home (10 hours with lay overs) and arriving at home. That was with very limited travel experience and having to be video recorded / mic'd up for 6-8 hours a day to interact with multiple tech presentations. Basically very stressful for someone who never did any of that before and is generally not that outgoing.
I never really felt too tired in the moment and I know for sure I didn't sleep the first 2 nights and did get a few solid hours of real sleep on the 3rd night. Honestly I was pretty surprised at how well things turned out. I used to pull a lot of all nighters as a teenager playing video games. Usually by ~36 hours I felt some side effects like brain fog and being ridiculously tired but by the end of that stretch it was a way different (and worse) experience than that travel experience, or laying in bed for ~6-8 hours with my eyes closed at night but not sleeping for a few nights.