Yes, in this context, Stockfish is a kibitzer.
If fact, any engine can be a kibitzer.
Note that many GUIs (interfaces) don't use this term (kibitzer) at all, although they are, of course, capable of loading engines that can evaluate positions and offer lines.
According to chessbase, a kibitzer is an engine that can evaluate position and offer lines. stockfish has recently become the highest rated engine. So I would like to ask if stockfish is a kibitzer. If stockfish is not a kibitzer that what is?