Tooltips don't work when using the system with touch, and these here are also a bit annoying with a pointing device since they appear instantly on hover and take up a lot of space, so they unexpectedly pop up and cover UI elements a lot.
To improve this, use a
KCM.ContextualHelpButton inline in the list items
to show the explanation when clicked or hovered, just like we do in most
other places in other KCMs.
To make this work, the internal line breaks in the explanatory text had to be removed to make the text flow properly with an arbitrarily-sized tooltip.
Ignore the extra empty area on the right side of the
ContextualHelpButton tooltip; it's a bug in the component itself that is fixed in Qt 6, as used by Plasma 6 which this targets.
If and when this is merged, I also plan to massage the text of these explanations a bit.