As long as you buy from reputable and transparent companies you’ll get products that are designed to perform very closely to the Harman curve and minimal distortion/modulation whether that’s the “ideal” curve is debatable ofcourse.

People often argue with “oh but you can EQ other non-professional brands to the harman curve at well”, but you’ll need to take in account the sudden cup resonances and driver limits and air pressure (think lower frequencies) issues you’ll be inevitably running into.

In the end graphs aren’t everything as seal, materials, drivers, angles, damping, pressures, air dissipation, resonances etc. all play a part in it, don’t even get me started on how complex good speakers can be.