That's why I specified Ultimate newcomers. What newcomer other than Joker was revealed outside of a Nintendo or Smash direct? Joker had the excuse of not only being the day before Ultimate, but also on a world stage video game event.
One direct you pulled up from 2017 is not what I'm talking about.
When I say Nintendo Direct, I meant the ones that cover multiple games quickly. Something along the lines of the April 2017 direct.
However, the May 2017 direct focused only on Arms with a small (around 2 minute) segment of Splatoon 2. The wikipedia article's timetable makes sure to separate these two types of directs with white and yellow colors. In recent years from 2015 to now, the only big worldwide directs that cover multiple Nintendo games at once and were not E3 are:
Jan 14, 2015 - Revealing the New 3DS
April 1, 2015 - Standard Affairs
November 12, 2015 - Standard Autumn Affairs
March 3, 2016 - Not sure why there's no direct in the latter half of the year
April 12, 2017 - Standard Spring Affairs
September 13, 2017 - Standard Autumn Affairs
March 8, 2018 - Standard Spring Affairs
September 13, 2018 - Standard Autumn Affairs
February 13, 2019 - Most Definitely Standard Spring Affairs (even though it's technically winter)
Yeah. They space these things out for a couple of months. In 2015's case, they wanted to reveal a new system, which would on it's own require a direct. If you wanna expect they'll do something late April with the information I provided, go nuts. From where I'm standing, any grand info that would be available in April or May would be better saved for E3. It seems they've found their groove for now and it's logical to trust in it.