freeing up storage in older systems

Here is what Apple has told us about that "Other" storage.

The Other Category should not be altered, modified, move or deleted since it is part of the Mac’s operating system. Doing so would corrupt the OS and render the OS inoperative requiring a Wipe and Re-Installation.

The Other category is a potpourri of files which include:

• System temporary files

• macOS system folders

• Archives and disk images (.zip, .iso, etc. - often found in the Downloads folder)

• Personal user data

• Files from the user’s library (Application Support, iCloud files, screensavers, etc.)

• Cache files

• Fonts, plugins, extensions

• Other files that are not recognized by a Spotlight search

• Media files that cannot be classified by Spotlight as a media file because they are located inside of a package

They can be located anywhere on your hard drive. The files that you have control over are located in the Documents, Downloads, Pictures, Music and Movies folders.

Also, if your OS becomes too full your computer will stop functioning. As I suggested earlier, this is a good time to add an external drive for storage. Then you can move files onto it and then delete them from your HD to clear needed space. Easy to do and problem solved. That is what else you can do.

What is “Other” storage on a Mac, and how can I clean it out?

In Monterey the “Other “ category is named “ System Storage “.

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The final word from Apple on Managing the " Other " Category

Other: Contains files that don’t fall into the categories listed here. This category primarily includes files and data used by the system, such as log files, caches, VM files, and other runtime system resources. Also included are temporary files, fonts, app support files, and plug-ins. You can't manage the contents of this category. The contents are managed by macOS, and the category varies in size depending on the current state of your Mac.

You cannot do anything with the "Other" storage. It consists of the Mac's various files and messing with it would cause serious problems. You are right to know that freeing up storage is important. If your disk gets too full your system will lock up and stop functioning. You need to eliminate files to clear space. You can either delete them or install an external disk so that files can be copied onto it and then be deleted from your hard drive to clear needed space.