That is misleading. Although you're technically correct [1], the computational models on which computational complexity classes are based are so abstract and idealized, that they offer almost no information whether your program could make efficient use of an actual, physical 8-core CPU.

The NC complexity class assumes a PRAM machine, in which all processors can access all locations of a central memory in constant time. That's not how a multi-core CPU works in practice: If your parallel algorithm doesn't make proper use of cache-locality, you've already lost.

[1] (the best kind of correct)