Yes, you definitely going to have to take care of that problem not only for Sims 4 but for Windows as you may start noticing slow downs as Windows prioritize what little resources it needs to keep Windows running. As others are saying you might want to get an bigger hard drive or SSD and if you system can has the capability install an second drive and install Sims 4 to that drive however the core files must remain on the C:/ drive and Sims 4 will do that automatically. Another thing to keep in mind do not fill up an hard drive to the max and that goes more importantly for SSD drives as SSDs act differently than HHDs. Sometimes programs move blocks of info across the HHD or SSD and problems arises when it can't do what it needs to do. I myself keep my drives under 75% full.
