The following information comes from a GamesBeat interview with David Young, Nintendo of America’s assistant manager of public relations:
"I can answer that we’re not going to be using Miiverse for Nintendo Switch."
Young said that the lack of StreetPass plays into the idea of the Switch as a home console, not a portable system (even if it offers on-the-go playing). Miiverse is Nintendo’s take on a social media platform for both the Wii U and the 3DS. StreetPass is a 3DS feature that let players exchange game data when they passed other 3DS owners in real life.