Not everyone finds their time very valuable. Also I dont think there is a proper definition of a fulfilled life. There is no definition.
My personal view is everyday we go to sleep, we are as good as dead. It is like we close all our trades and position is zero. Next day when we wake up(if we wake up), it is a new day and then since we have the day in front of us, we need to fill it somehow. Different people fill their days in different ways, some people dont have enough time, some people have crazy amount of time and the time just doesnt move.
But in the end, the day does get over and no matter how you spent it, it really doesnt matter. You go to sleep and you are dead again, whether you are Bill Gates or a monk or a criminal, everybody's day eventually ends.
So it really doesnt matter in the end. Sure it matters while we are living our day, how we live makes us happy or sad, but that is only because we lived the day. If we didnt live, it is just neutral. So we can say, some people who have very sad lives might say, we would rather not have lived this day at all. So you see time is not equally valuable and I would say in this world majority of the people are not lucky enough to have great days. Very very few are fortunate. But even that fortune only stays until the day ends.
Our whole life is just a combinations of 100s of such days. It is as simple as that, we just make it very complicated