I would like to prevent Obsidian from expanding the contents of a folder when I click on the folder name.
I don’t think this isn’t currently possibly via some Obsidian setting, but you can try this: Right-click a folder then press Esc (or instead, then click the Files tab button at the top, or in the left-most part of the sidebar). It will leave the folder selected without changing its expanded state. If you just want to select the last item you selected in Files, bind a key to hotkey “Files: Show file explorer”.