If it is the same video I saw, it seems like they were set somewhat haphazardly. Although, there have been so many different things posted over the last few days it may be a different video.
One thing to consider is the size of snapshot on disk is directly related to how much data has changed since the snapshot was taken. This means, generally speaking, that the older the snapshot, the more space it takes on disk.
So, given a reasonably typical rate of data change on a desktop, a snapshot from the last 24 hours will take up almost no space at all but a snapshot from 2 years ago will probably be taking up quite a lot of disk space.
That being said, here is how I configure mine for machines that are on most of the time:
- hourly - 24
- daily - 7
- weekly - 5
- monthly - 12
I may not do all of that depending on how much the data changes and how important it is. For example, on my root volume I stop at weekly. A month’s worth of snapshots is plenty there. On some volumes I do even less, only keeping the daily or hourly snapshots.