My Macbook is full of system data.

It's quick to find out what kind of files are actually consuming capacity.Even if the system data is being consumed, what is large in the breakdown depends on the environment and conditions.It may be the data you really need, or it may be erased like a cache.

First, "About this Mac" → "Storage" → "Manage Storage" provides a list of large files.

Also, if you can install third-party tools, you may want to use them as they are known.Several tools are known, including OmniDiskSweeper.See this list: https://apple.stackexchange.com/a/5360/360444

You can also check the command line without installing the tool.duThere is a command to check disk usage, so you can use it to check:

 sudo du-h-d1-c-x /| sort-h

(However, starting with /, it takes a considerable amount of time.)

Related

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