I mostly lurk on these forums, and use it to look up rules questions, and generally check in on Shadowrun stuff. I have not read every page of this thread, but read the start and the last couple pages. I think there is something that is concerning here, to me.
First, opinions are opinions. Some people will like the direction they went with in 6e and some will not. There were some that stayed with 4e, and that is fine. I personally like the concepts and what they were going for in 6e, but that is only my opinion.
However, the ratings should be concerning for one important reason. The 6e Core Rulebook is objectively a really really bad book. There are numerous errors that can only be due to editing, and lack of play testing. I am not talking about "This is OP, that feels wrong, Armor does not have enough of an impact", I am talking about contradictions in rules, some rules left completely out, things that everyone here knows about. The errata team is hard at work to correct some of these things, but they are there in the product and they are for the most part unforgivable things for going to press. To ignore these things and try to discuss why the ratings are poor is to stick your head in the sand to the issue that we all know is there in front of us as it has been well documented here and across the internet.
Adding to this many of the rules implementations are objectively inconsistent. None of this is news to anyone in these forums.
And those things are not opinions, they are concrete things that can be pointed to. Now, if the rest of the book makes up for those mistakes TO YOU, well that is fine, that is opinion. That can cause someone to rate higher. But to have a book so riddled with clear mistakes and to be released in such a poor state, then have it trend mid to low on review ratings, and try to rationalize that out, well. Ostrich on, my friend. It is pretty obvious that the mistakes have impacted people's opinions on the book, as it should. Even if you love it, you cannot say it is better with these mistakes than if they took more time to edit, and have it more cohesive and clear.
Now on to my opinion, since no one asked for it. This book was the single most disappointing rulebook I ever read. Now most of that is my love for the genre, getting behind what they were trying to do, and too eagerly anticipating the release. My local groups shadowrun campaign was put on hold for this, as we waited a couple months. The release came and several of us had purchased the deadwood book + pdf so we downloaded and read through it. Initially there was some confusion but we optimistically got together to make test characters to go through a one shot to test out the system (5 players + GM). The system did not last through the one shot before we pretty much unanimously decided that it was a complete disappointment. We decided to wait for a few more erattas were put out. After a couple weeks of us trying to homebrew some solutions to mathy problems with the system and inconsistencies one of my core beliefs kicked in "If you have to homebrew a system extensively, you are using the wrong system. Switch to one that more closely matches the flavor you want", so that is what we did.
I am a big, big fan of some of the things they were going for. But overall the flaws (real, hard, objective flaws, not opinions) have a major impact for me. Combine that with the inconsistencies (which, hey, could be part of the editing flaws) and the results when you math things out and the game hits the table, a major failure in my opinion.
But I will continue to check on updates. If there is another revision, more clarifications, etc. Hopefully eventually a pdf I can download that has a lot of the problems fixed. Unfortunately I have a hardcover paperweight that I wish I could return (even if I did not get money back. I never ever will use it in it's current state.)