I think 6-8 potentially deadly encounters per day is...extreme. Like, on the extreme end of the extreme spectrum. Like only matched by the most gonzo action movies, extreme. It's God of War or other metroidvania style games style, where you are expected to just kind of not think about how incredibly exhausting this would be, and how you'd need weeks of rest to recover from just a couple such days, if you somehow managed to survive.
I mean, imagine doing a really, really, brutally, intense martial arts competition with full contact combat, every day, for a week. You'd suck at all physical activities by the end of the second day, if not before that. In dnd terms, you'd be making saves against exhaustion every day, and eventually every fight.