@Tell and
@sigbergaudio
Your concerns about using NS-10s in studios seem to be based on the misconception that a single pair of speakers is the only thing used throughout a whole audio production. However, that is usually not the case, the NS-10s were mostly used as one of many tools during the mixing process as it was found to be highly revealing of possible faults in the important midrange area. A more bass-capable speaker is of course used to be able to hear what's going on in the bass area of a mix, and a more balanced and full-range speaker system is of course used in the mastering process to be able to hear the overall balance of the whole frequency area.
Even if the NS-10s have a wonky frequency response and not the full bass extension, it has other qualities that Bob Clementine and other good mixing engineers found to be useful, especially for the midrange area where pretty much every sound object occupies and shares in a sound mix, which is, therefore, the most critical frequency area to get right if the mix will translate well to most playback systems out there.
Not everything in audio production is dependent on a flat-frequency response, there is way more to it than just getting the overall balance right.