Rock Band 4 not coming to Wii U because "the audience is not there"

[Kerotan]

mysteryman said:

More info from a FAQ on the Harmonix forums

Q: Why not Wii / Wii U / PC?
A: Due to shifting production priorities and capabilities of the studio, we don’t currently have plans to release RB4 on the Wii / Wii U / PC simultaneously with Xbox One and PS4. While we genuinely appreciate the support of Wii Rock band users over the years, and the increased interest from PC gamers, the truth is that we had to prioritize opportunities on other platforms with historically larger RB audiences.

Wasn't the Wii a historically larger RB audience than PS3?

It sold slightly more on a much bigger install base at the time.  Meaning that it would sell a lot more on the ps4 than the Wii U considering the tables have flipped.