Paid Time Off is a funny thing. Workplaces act like it's a finite natural resource and not something that can be pulled out of thin air if necessary. Of course, not everything necessitates taking PTO. If someone wants to go on a month-long vacation, they can't just get extra PTO because they want it. They need to save it up! However, there are some extenuating circumstances that necessitate having some leniency with workers taking a little extra time off. There is a reason why some companies differentiate between sick leave, vacation leave, personal days, and bereavement leave.
One worker recently went viral on Reddit for sharing his coworker's story. His coworker's wife was dying of a brain tumor, and the company asked fellow employees to donate their PTO hours so he could spend time with her in her dying days. I really can't think of anything more heartless than that.