In an article from the Washington Post, it turns out Nintendo realized their secretive marketing wasn't working and threw together that 13 minute gameplay demonstration in April as a response to the lack of enthusiasm.
https://www.washingtonpost.com/arts-entertainment/2023/05/20/eiji-aonuma-zelda-tears-kingdom-producer/
I mean, who would've thought, people actually wanted information about the latest Zelda game lmao
Good to see they recognized their error at least.