I can agree that the line can get a little blurry when talking about a console and how it can become computer-like. Keyboards can be added, and even OSs installed for other applications these days. There was even a (very crude) BASIC for the Atari 2600.
However, I don't think you can go the other way around, without manufacturer intervention (CD32). The C64 might come closest because of it having a huge library of excellent games but nevertheless it certainly did more than games and the like, even if not well.