don't you think that music "live" in a studio sounds exactly the same as playback,do you think there is any difference in sound quality ...?

Not usually, no, but then that's not usually the intention.

If you sat in a studio with someone actually playing an acoustic instrument like guitar, piano or drums you would hear the whole sound of the instrument. It would also be affected by the acoustics of the room and, despite the fact that the room had been treated to reduce reflections and colouration you would still hear some sound from all around you. The playback will be what a few microphones "heard", will have been compressed, eq'd and treated and then played back through speakers.

Even using a different mic or playing back through different speakers produces different sounds.

No. Recordings are heavily influenced by the mic, mic position, preamps, and the mixing involved. A live performance is perceived in 3D space and affected by the acoustics and distance from the sound source.

digital