My home computer is on 24/7. I do some production on it but not nearly the amount I would do in my studio. That being said, it won't really hurt the computer to leave it on. Occasionally a fan will need replaced but that is really the only issue I've had a problem with in the decade or so I've been leaving it on and realistically, it depends on the fans. The better quality the fan, the longer the life. Case fans are always the first to go because of the type of bearings they use which are typically the cheapest they can get. I occasionally reboot the computer because sometimes Windows will bog down over time, but it boils down to how well you take care of and clean out files that cause issues like that.
I will also mention that my VS-100 is my interface on this computer and it too stays on 24/7. I do have concerns about the internal fan on it because eventually it will go, I'm sure and I don't know if I'll be able to get a replacement for it so I've thought about buying a backup while I still can but I have a feeling by the time it does go, I will have switched interfaces due to lack of technical or driver support.
The studio is always off and unplugged unless I'm using it. One, because it's a waste of electricity leaving all the equipment on. Two, because I'm not always around to unplug everything if we get a storm.