Nope. You're wrong. This article has nothing to do with the creative process of coming up with presentation content. It's just a quick tip that might make your life a little easier in a web conference, webinar, or webcast. Number your slides from 1 rather than 0.
This is particularly important if your web conferencing technology uses a PowerPoint upload step that treats each slide as an individual entity (a la Webinato or the "File Open and Share" option in WebEx). I see a fair number of client presentations that start slide numbering from 0 for the title slide so that the first "real content" slide comes out as number 1. The problem is that the slide navigation controls in the webinar product number the slides from 1. So if a presenter wants to show what she thinks of as slide 23, she has to select slide 24 from the webinar navigation controls.
It's not going to make or break a presentation, but if the slide numbers are consistent everywhere you see them, it's one less thing you have to explain to someone coming in and trying to master the technology.
I started to write that if you show your slides in a web conference via screen sharing (a la GoToMeeting or Zoom), you can ignore this tip. But it turns out that PowerPoint itself is subject to the same navigation problem!
You may be familiar with the fact that when displaying slides in Slideshow Mode, you can jump directly to any slide by typing the slide number and pressing the Enter key. If you try this trick with slides that start from 0, you end up off by one. As a matter of fact, typing 1<Enter> or 0<Enter> both bring you to the title slide.
If you don't know how to change the starting slide number, it's because Microsoft hides the control in a ridiculously non-intuitive spot. In PowerPoint 2016, go to the Design tab and click on Slide Size. Choose the option for "Custom Slide Size…" and you will find the entry for "Number slides from:"
You'll have to ignore the fact that slide numbering has nothing to do with slide size. They just couldn't figure out anywhere else to put it.
Whether or not to show slide numbers on your presentation slides is an entirely different discussion. I'm generally against it except in training and reference situations where you expect participants to ask you to return to specific slides in order to discuss examples and information.