Quick update, probably user error.
I misunderstood "Restart NodeBB" to mean restart the process. When using the Restart button on the Dashboard and uninstall/reinstall the plugin works as expected in the simple case.
Sorry to bother y'all. Thanks.
is there any plugins or ways to make social sharing icon more presentable or easy to find?
For this, you'll have to modify the theme to reposition or enlarge them.
You can also adjust the CSS using the custom html/css page in the ACP.