What word would you have used in place of "beauty"?
If the author had argued in favor of optimizing the visual look of your slide deck to maximize its impact on your audience (a rough paraphrasing of one of your sentences), I wouldn't have disagreed.
But if her first bullet point had been about choosing/buying the right font, I'd have demurred (and I say this as someone whose livelihood focuses 100% on the visual presentation of text!).
Aesthetics. The look/feel of your presentation - as much as possible it should feel aligned with your topic, evoke the feelings that you want from your audience, and help to emphasize the most important content.
I think the word beauty is fine. But the problem is that it means different things for different people. For example, something could be ugly and beautiful at the same time (like every single new born baby I have ever seen :P ). So whenever I see a word like that, I usually default to trying to figure out what THEY mean by beauty. And try not to bring any baggage with me.
If the author had argued in favor of optimizing the visual look of your slide deck to maximize its impact on your audience (a rough paraphrasing of one of your sentences), I wouldn't have disagreed.
But if her first bullet point had been about choosing/buying the right font, I'd have demurred (and I say this as someone whose livelihood focuses 100% on the visual presentation of text!).