Not even a mention for LaTeX? It's the obvious solution for non-typesetters to focus on the content and end up with a nicely typeset document. Although I suppose this is more about Butterick than typesetting.
On the value of good typesetting, there's empirical evidence that typefaces affect the credulity of a document. It certainly seems like that alone should do a good job of convincing a lawyer to care! That really makes me think that the problem is a lack of tools – and for that, LaTeX beats any individual typeface. Even Butterick's awfully nice looking faces will be mangled out in the wild!