I am a Physics student but also love math and music, and know a little bit about tuning because it is related to mathematics.
So as far as I understand, Just Intonation is more consonant than Temperaments.
The major problem of Just Intonation is modulation in instruments which can only play fixed frequencies like the piano or the woodwinds.
For example, the mainstream 12TET in western music can be considered as a compromise to make modulation extremely easy while the dissonance introduced is equally shared by every tone.
My question is, with modern technology and when music can be played electronically, it seems that we can solve the century-long problem of modulation and consonance of music now. Say, with an electronic piano we can play a song in a certain key in Just Intonation. Then when one needs to change key, the computer just immediately adjusts all the frequencies slightly so that we still have Just Intonation in the new key.
Am I right? And in fact is this actually what is already done in practice in electronic music?