What I want to say is this.
Yes the majority of 44.1kHz 16Bit MQA releases are different and to my ears and brain better than, the original 44.1kHz 16bit releases (but this is personal).
The MQA version is mostly more dynamic.

I can say no more than that, but do the comparison yourself.
Try Al Stewart Year Of The Cat. This album highlights the differences I hear and appreciate.

In answer to your second point, I would not be so presumptuous as to give an opinion on how this is achieved by MQA. Bob Stuart is your man for this question.

Best Wishes Hector

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