By far the dominant tuning system in Western music theory and practice, it doesn't reflect the tuning reality of many of those practices including American popular song and blues.  This is not because we are anti-technology. Our tuning is local to factors that the tuner, and the theory it reproduces, can't compass.  We 'sweeten' our tunings to sound the way we like them to on our various instruments, tune differently for different songs, and tune differently depending upon which other instruments we are playing with.