As far as the warts of MQA I don't know that anything will bring back an actual live performance of the Door's but when you sit down and listen to the MQA versions it just sounds so good to my ears. The FLAC sounds good, you don't even notice that digital brittleness in a good setup until you compare it to the MQA version. The MQA version through my system just sounds more relaxed and closer to an LP. I now understand why people are attracted to tubes as a way of softening that digital hardness and why album sales are going up. I think the standard to compare MQA to isn't the master file but the album. If I can get a streaming source to get me even 80%+ of the sound of a great turntable setup I think that is pretty good.
If you don't want to use the 2L test bench why not compare tracks using a turntable and let us know? I don't own one.
Maybe one difference between us is that I don't have digital brittleness in my playback - even without MQA. And why would I compare MQA using a non-digital comparison? Makes no sense. Especially as vinyl sounds inferior to my digital playback. I own a TT and vinyl, but don't use it - it simply is inferior to properly done digital playback, at least to my ears.
In my view the standard for comparison will always be the master file. An LP or any other altered version is just that, by definition - a less accurate, colored version that is less faithful to the original.
There are already people analyzing and reverse engineering MQA. One of the things they've found is that there are a set of totally conventional filters (various minimum phase filters) used to get the "MQA sound". You can upsample any CD, apply one of the filters (or a very similar one in playback software that offers various filters) and get the same sound.
You don't need MQA for that. There's no really special technology or special audio "discovery" involved. It's just a use of a certain type of slightly lossy compression, and then decompression (unfolding) and filtering to get a certain type of sound. Don't kid yourself. The long term goal is to get the consumer to pay more for the privilege of using MQA. They'll use marketing speak and a certain type of DRM to make sure you think you can only get "that sound" by buying into MQA. At first it will be "free", but not forever.
Do you think MQA and the record labels are doing this because they are altruistic? The whole process isn't free for them - they are going to want to make money on it. Don't fall for the MQA marketing hype. Read about what it actually is and how it works.
High end audio companies work hard to develop products that they think deliver the best sound. So of course many are opposed to MQA: if you had worked hard to create a DAC that sounded just the way you thought it should (and every DAC designer chooses some kind of filtering built into the conversion to analog stage), why would you want to pay MQA a royalty on every DAC you make for the "privilege" of using what you consider to be filtering that is at best not better, and at worst, inferior, to what you already use?