As someone else pointed out, the audio book with all the exposition and descriptions is 12hrs (I haven't confirmed this).

That person was mistaken. It has nearly a 30 hour run time.

The problem with this argument is "doing [something] justice" is highly variable. Justice to one is an utter disservice and disrespect to another. Instead of people talking about what actually bothers them about the show they try to generalize and guess at how to do X thing right. Oftentimes those people fall into mistakes like this, even when talking in good faith.

Compressing 12 hours into 8 would be difficult to "get right." Compressing 30 is nearly impossible. It's not even a particularly good comparison to begin with considering the audiobooks still have the same difficulties the original book has when it comes to adaptation.