https://www.forbes.com/sites/quora/2018/08/22/jeff-bezos-banned-powerpoint-presentations-at-amazon-meetings-heres-what-replaced-them/#f249f633b5f9
In my opinion, listening requires less brain processing power than looking at written sentence. If the sentence is reduced to only points, it will need even more brain processing to rebuild the points to full sentences to translate meaning. Thus, avoid ppt, use blackboard drawing to show systematic relationship and speaking to explain instead -- just like lecture in top university.
