I'm still in the position that if March 2024 isn't launch, the only other
viable option is a event like the Switch January 2017 one.
Thirds, especially "smaller" ones and indies that were seemingly the main focus of the Gamescom presentation, would neither need to know when Nintendo will announce it via PR ("To whome it may concern" style) or an "announcement" video like the Switch ones in ... October or November 2016.
Why would they even need to know about these two options?
The PR will feature no word on games. And the video would mainly show off one or a couple of Nintendo games, and maybe one big third party game like Skyrim.
Plus, the funny thing is, even for the video, thirds wouldn't need to have software ready. A short gameplay video, captured on PC or literally any other platform would be enough, video editors don't need more to edit in.
Also, you can bet that big thirds are already in the know for longer and wouldn't need to attend a Gamescom presentation for this.
So yeah ... it's either launch, or a Switch January 2017 like event.
PR and "announcement video" will imo come before March 2024. But that doesn't necessarily mean one of them happen in 2023.
You will get that one, definitely.
Now the question WHEN you're going to get it ... hahahah that will be a couple of years of waiting. ^^