The runway discussed may have been suitable. Sometimes it swings the other way and the book says you can do it. Does not mean you actually will be able to do it. Eg in video.
The whole thing may have been perfectly safe and within spec. We only have one anonymous pilot few of us know anything about telling us the tale. There is no w&b, no book and no runway length or slope data to go on. The stall warning tab may have been positioned in a high position, I believe there is adjustment on the tab.
Those who bag out this pilot on the available evidence must have taken a lesson from the regulator.