I still fail to understand why the general Public didnt burn their Simcards for him. These 21 Points still hurt.
Do you want the short or the long explanation??
The short version: Viewers simply didn´t like it.
The long version: As you often pointed out both performances were technically perfect, but sometimes
too much perfection is also hurting. The song and performances seemingly came across as pretty sterile and distanced. Another factor was maybe Benjamin himself and how he acted during his performances. It´s pretty difficult to find the right level of self confidence, what seems self-confident to one person can look for another person more self-regarding, and it seems that most viewers fell in the second category.
Beside that I think viewers in 2018 just wanted something completely different. I still hate "Toy", but it was a winning title different to any other. Sweden on the other side was maybe more like "radio friendly dance-pop part 350" for them and therefore not interesting. Maybe there was also some kind of "Sweden fatigue" among the audience.
These are at least my theories.