I think the solution "just empty out the label text and use the "static text" special control in the form definition" is the canonical answer. We should avoid manual code as much as possible.

Labels are meant to be small titles associated to input fields, not whole questions that are better represented as data than as interface text. The Label pattern does not offer that functionality.

One solution is to work with the css styles to create a class that will provide word-wrap and will force a max-width to the field. The minor details for respecting interface responsiveness to multiple screen sizes are hard to determine, but should be something like:

.multiline-label label {
    overflow-wrap: break-word;
    max-width: 150px;
}

Then in the form editor you can set the "style" property for those controls. But you will have to tweak things around, especially with the pixel width until you get acceptable results.

Another solution is to just empty out the label text and use the "static text" special control in the form definition. There you can try to control the line-breaks with html br elements. Remember to activate the "html?" option.