Mac_at_the_shore wrote:
[...] How do I reduce the system data stuff to a more reasonable amount of space? Laptop is running Sequoia version 15.7.3.
You don't. The new laptop's 256 GB drive is too small for proper management of personal and system files. you'll be playing 'whack-a-mole' trying to keep things under control for the life of the computer, imho.
If you bought that new MacBook directly from Apple, then you have 14 days to return it for refund. Do that and then buy another with a 512 GB drive or better.
I don't understand why Apple continues to sell any mac with such a small drive in today's environment of large and powerful OSs and apps.
A more direct answer to your question -
'System data' is an amalgam of files that don’t easily fall into the defined categories of “Audio" “Movies” “Photos” “Apps” and “Backups”.
You can’t directly manage the contents of system data. That is done by macOS. The category varies in size depending on the current state of your Mac.
What you can do to create more free space:
• Empty the Trash in the Dock.
• Empty the trash in the Photos app.
• Delete unused and unneeded application installers from your downloads folder and desktop. No need to store on your Mac what you can freely download any time.
• Reboot your Mac at least weekly. Let the OS do its housekeeping.
• Transfer files that you don’t use daily to an external drive and then delete them from the startup drive and empty the trash. Files that take up the most room are movies, images and music.
This from Apple on the subject of freeing up space:
Free up storage space on Mac - Apple Support
Also, please see the following guidance from Apple:
Find and delete files on your Mac - Apple Support
