To color grade 4K footage, a 4K monitor is not required. All you need is a decent 1080p monitor that can precisely replicate the color ideally through color calibration. In many cases, 1080p takes far less memory storage than 4K.
This frees up space on your editing hard discs by allowing you to record more clips to your memory card. 4K cameras frequently necessitate significantly quicker and more costly memory cards. The reduced file sizes of 1080p video are advantageous.