Another big thing I want to bring up is why Nintendo usually doesn't do huge presentations in July or August, especially in the middle of the month:
https://www.jrailpass.com/blog/obon-festival-in-japan
Obon is an enormous deal in Japanese culture. It's like if you combined the American Thanksgiving with the 4th of July: lots festivals, lots of traveling, tons of people taking vacation time, culturally one of the most important times of the year, etc. Usually they give both times a wide berth for major announcements because it's supposed to be a solemn holiday too. For example, this is probably why Hero was released at the absolute end of July last year and why, two years ago, the Smash Direct was super early in August.
Sure, they could do a presentation in early July but that's still cutting it close. Even outside of Obon, July and August are huge vacation months around the world and let's just say a lot of people are kind of distracted anyways. Has Nintendo released things near Obon? Yes. Has Nintendo ever made major announcements near Obon? Not that I can think of.