Ncdu takes ages to run on my system, its like 500GB+ of storage space, but it takes roughly an hour to finish scanning, probably a bit less, is there any alternative which either constantly monitors my files so it always knows the sizes for me to navigate or is significantly faster than Ncdu?
If your filesystem is btrfs then use btdu. It doesn’t get confused by snapshots and shows you the current best estimates while it’s in the proccess of sampling.