This is a misunderstanding of what you are adjusting, the idea is you EQ back to what would be flat in an anechoic chamber, which produces a slope in room.
Yes and no. What is termed as “room equalization” procedure (not just the auto-tuning) compensates for several things at once (even if it is not marketed as such because only one of those reasons works well as a marketing message).
1. The non-linearities inherent in the components in the audio chain (particularly speakers) independent of the room characteristics that will exist in an anechoic chamber as well with the same equipment and will need correction. This can be seen as a move towards perfect reproduction with less than perfect equipment. This just brings it closer to whatever target curve one chooses but not influence the target curve itself.
2. The room absorption and reflection characteristics that would not exist in an anechoic chamber. This can also be seen as a move towards perfect reproduction but there is anecdotal evidence that this by itself does not result in perception as good sound. While this might set the general characteristic of a target curve, there is no “single curve that fits all” as would happen if the goal was just to replicate an anechoic chamber.
3. A human ear’s varying efficiencies across the spectrum which would also exist in anechoic chambers. Outside the auto-tuning features, the systems allow the target curves to be modified with more slope, or more or less “room gain” in the lower frequencies, altering the slope at higher frequencies, etc to what one perceives as better sounding. This need would exist even if one was listening in an anechoic chamber.
There is anecdotal evidence that a single slope does not work for everybody which would appear to suggest that people don’t necessarily have a preference for exactly what they might hear in an anechoic chamber with perfect transparency to necessarily choose that in a well-designed blind test. Choosing that strict criterion is more of an “acquired taste” for intellectual reasons and hence subjective while attempts to achieve that might be objectively conducted.