Why are high power, all the stops decks not part of high power casual EDH? Can you give examples of such decks?

Sure zerowner! An example is also given in chapter 2.3, but here’s a more complete answer:

The boxes show the boundaries of where decks may become unfit for the table and may start to raise objections from fellow players. The guide states that, in general, odds are that the lower you go in power level, the narrower the tolerated range of interaction impact becomes. A common deck that’s high power and max interaction impact is a high power Tergrid, God of Fright  ^Flip deck. That’s a typical deck where you might want to do some extra alignment on expectations with the people at the table to see if they can tolerate such a high interaction impact at that power level.

What’s also stated in the “about this guide” section and in the primer is that the boxes aren’t meant as the correct definitions of these format interpretations. They’re just a starting point for the user to define and express their own preferences, and to assess the type of game that the table prefers. Also, the point of the boxes is not to say that these are the 4 only options (putting in all the possible different boxes at once would not be possible). The point is that this is a way to gauge the table expectations and that there are many other boxes possible. These 4 are just an example and a starting point.