Migrating from Synology Photos to iCloud (2TB capacity), but too slow to upload 59000 photos / videos to iCloud using Macbook Pro Photos

As I migrate all my photos / videos from my Synology NAS using my Macbook Pro as the upload point, it is just taking too long to upload via Macbook Pro's Photo App.

• 2Gbps connection with 1Gbps upload
• i7 Macbook Pro
• 2TB iCloud capacity
• 170gb of content = 6000 videos + 53000 photos
• I am getting an average of 500 to 600 items a day uploaded to iCloud. At this rate, I'll need 3 months

What do I tune this to get better speed?