Not talking about Nintendo. I'm talking about the other consoles and systems. A lot of the games shown at E3 for them are supposed to releasing in Q1 of 2019. Hence, that is why Yoshi may get overshadowed as gamers may be looking at some of those titles for purchase ahead of Yoshi. If people have a Switch only then it may not be that a big a deal since they won't have those options but other gamers might.
As for the other games, you mileage may vary I suppose but I would take Yoshi over Let's Go Pokemon or Super Mario Party. I think it's bigger than either of those although I'm sure Pokemon will prove to be a hot commodity for many others. Still, to say that Q4 is crowded because of 3 games doesn't seem like it's overly crowded to me.