There's no such thing as "HiRes audio", having more bits per sample is just lowering the noise floor which is already well below human earing threshold using regular CD quality. As for using higher sampling rate, same applies. 44.1 Ks/s was problematic when CD came out because filtering was using very high order brickeall analog filter. It was resolved long time ago using ouversampling. This is basic undergrad knowledge for digital finit bandwidth signal theory, don't listen to peddlers...
As for MQA, it is trying to give another spin at their false claims, being a lossy and closed source / royalty "audio fool" codec... As for their (again false) claim to provide "better tool for encoding", that is complete BS... Huge majority of music is recorded digitally and we already have open source FLAC codec for lossless and high quality MP3 codec (LAME is very very good!).
Never forget the most important: Audio quality is a direct function of the quality of the recording process and mixing by a talented audio "engineer". The rest of the chain has very very low influence on the result...