It would be a bit boring (at least to me because I always love seeing more NPCs) but it's certainly a possibility.
Okay this may be a bit of a stretch but...
This scene here, from the Japanese trailer, with the 8 silhouettes on the upper wall which could very well be silhouettes of the Gym Leaders... I don't think those names underneath are names of (some of) the Gym Leaders.
GameXplain pointed out in their analysis video that the orange-shirt boy who is friendly towards the new kid picks the starter that is weak to his, which lines up with this new character. In the video, he says his name is Hoku. Hoku is one of the names on the wall. I think those other names may be more similar characters.
I think we have a group of friends again.