Experience with large libraries and the MediaBay

Are there users who manage terabyte sized audio libraries in the MediaBay?

I have a library of almost 6 TB of audio and MIDI data (this is not the topic). After the first scan (which took several days) the hard disk had several damaged sectors - I thought the disk was defective.
So I got a brand new external LaCie Thunderbolt 3 disk, and once again the scanning process (almost a week) seems to go on and on - and now it’s no longer possible to write to the disk, rename folders or empty the trash (neither Apple nor LaCie could help). Now I have to format the disk and restore a backup (this is going to take days again). I guess that Cubase just can’t cope with this amount of data.

Does anyone have any experience with it, especially under macOS?

Or is there more information about what the scanning process exactly involves or what it does on the disk?