Here is an edit (including a SOLUTION!) to my above post, since it wouldn't let me edit it for some reason...
I found a good website that digs into what all GarageBand is using:
There, it essentially shows four folders where things are that GarageBand uses (part of which are the Apple Loop files I came across). These are some things you can delete if you DON'T want to use GarageBand. You may also want to keep the Apple Loops files and Logic folder if you use Logic Pro.
Here are some of the things you can possibly get rid of (but do so at your own risk!):
- Macintosh HD/Applications/GarageBand.app (1.16GB)
- Macintosh HD/Library/Application Support/GarageBand (995MB)
- Macintosh HD/Library/Application Support/Logic (880MB)
- Macintosh HD/Library/Audio/Apple Loops (up to 10GB)*
*Note that the size of the Apple Loops directory will vary depending on the number and type of loops downloaded by the user. You should not delete this folder (or the Logic folder) if you are using Logic Pro.
After I deleted the listed items, I went back to storage management and it said that GarageBand was only using 12 KB which was down from over 2 GB!