zypper remove --clean-deps removes automatically installed requirements when removing a package. zypper packages --unneeded will show a list of packages no longer required.

Setting solver.onlyRequires to true in /etc/zypp.conf does not install recommends - it’s way less of a problem than on Debian/Ubuntu due to not recommending half the world, but still useful. Setting solver.cleandepsOnRemove will automatically remove automatically installed deps when removing a package (i.e., like always specifying --clean-deps).

Just get a drive from any old notebook of the last 15 years or so someone wants to throw out, and buy a USB to SATA slim cable.