A synthesis of Carl's, Nick's and Joel's comments make sense re MQA and other MQA-aware digital processing within a closed (e.g. Meridian/MHR) architecture, including MQA-aware room correction.
There will be those whose room demands correction more than MQA (and I think, based on past comments and conversations, Joel is one of those). That seems to point to a theoretical integrated Meridian MQA/MRC solution. But implementing that, and the fact it would have to work across all analogue, all DSP, and mixed speaker solutions, and across multiple multi-channel (5.1, 7.1, etc.) and multiple object-based speaker layouts is clearly highly complex.
These debates really do help me (and, I hope, others) understand why we are where we are. Thanks for your input.