I might be misunderstanding the author but when I go to flight booking websites (such as google flights) then I have to select start + end destination + date(s). I usually only get back 10-20 results in total, but even if they did return more then I fail to see the complexity. Maybe there is another way to book flights that I’m not familiar with?
Nevertheless, it was an interesting article, would’ve been nice if it also revealed the pricing of these services.