Because showing the folder size requires scanning all the files in it, as well as all the files in all it’s subfolders. For some folders that could mean tens of thousands of files. Which would take quite some time.
There are ways to speed that up. But you’d be scanning all the files, all the time to keep a database updated.
This. macOS does do folder sizes. It rarely shows because it takes forever. Maybe if the drive was formatted APFS it would be faster? Not sure though. My drives are NTFS and exFAT.
Because showing the folder size requires scanning all the files in it, as well as all the files in all it’s subfolders. For some folders that could mean tens of thousands of files. Which would take quite some time.
There are ways to speed that up. But you’d be scanning all the files, all the time to keep a database updated.
Basically, it’s a lot of overhead
This. macOS does do folder sizes. It rarely shows because it takes forever. Maybe if the drive was formatted APFS it would be faster? Not sure though. My drives are NTFS and exFAT.