If true, then better to let it go than to keep throwing money at it. It was well worth the cost while it was in use, and now it's time to retire it and make room for the next thing.
Not a waste at all. Think of it like a car that you buy and maintain for years, then eventually replace. The money you spent on it while it was carting you safely around town wasn't a waste, even when it isn't the car you drive anymore.