You could say the same about many things. My car is idle most of the time. I usually only use it for 1-2 hours a day during the week and less on the weekends. I could use Uber or Lyft instead but I don't. I could rent out my car when I am not using it but I don't. It is idle because I want to use when I want to use without coordinating with anyone.

The same is true of my computer. I once worked at a Unix shop where people would routinely log into other peoples computers to do builds. It locked the machine up (this was in the 90s) and made it hard to do anything else on the computer. The whole point of a personal computer it to have all of the power there for your use when you want it.