The game Blizzard just released, Diablo 4, was the “best-selling opening in Blizzard’s history, crossing an auspicious $666 million in global sell-through in the first five days following its June 6 launch”. https://investor.activision.com/news-releases/news-release-d...
I don't think I've heard sell-through used before as a metric in that way, typically I recall seeing it as a percentage such as 80% of units shipped to stores have sold through to consumers. Units sold is what I typically see, like Diablo 3 at 30mil. Maybe sell through here means people buying platinum/cosmetics as well?
This places it among the fastest selling video games of all time (https://vgsales.fandom.com/wiki/List_of_fastest-selling_vide...) so yes, it’s just sour grapes from you.