"To illustrate this point" means to give an example or provide evidence that supports or clarifies the specific idea or argument being discussed. Full definition
So an article which illustrates its points with relevant in game screenshots is much more appealing than one that's merely a giant wall of text with nothing to really break it up. (gamingreinvented.com)
Of course if it helps illustrate a point in your lesson, then that's even better. (talentlms.com)
The dynamic content presented here illustrates that point by showing separately the projected temperature ranges for a given choice of climate sensitivity (with uncertainty due solely to radiative forcing). (giss.nasa.gov)