Is it possible to hustle all the time & not burn out? Yes, but it takes a special type of person who values the hustle, in and of itself, which is rare.
It's important to realize that there's no right or wrong with what you choose to value.
And, as an employee, changing your org's values is probably an impossible task.
Instead, get clear on what your values are. Then, find an environment where you're surrounded with people who share your values. You'll be much happier.