For the record, I agree with you on User scores, and I think Professional reviews are more reliable but with an understanding that they, too, are deeply imperfect because of the way money works in the games journalism industry and the pressure it causes on journalists. I have a few friends who work in the industry and my boyfriend quit the games journalism industry due to such pressure (to review/score lightly, to change scores, etc) - he went back to school and learned to actually make games because writing about them objectively was quite difficult. I will note the pressure was less on what he wrote than the score. They had no problem with him writing what was essentially a 6.0/10.0 review as long as he attached an 8 or higher. Now, the industry has improved in terms of being much wider due to Youtube, etc, but it's mostly an issue of advertisers basically being the same people you are reviewing. I don't think there's the kind of massive, seedy corruption some people mention, but I definitely think it makes sense that there is pressure. I've heard this from multiple people in that situation.
This isn't proof, of course, but it is a perspective.
There are a few review sites I use to seek info on games, but as the thread OP indicates in the links, there is so much false information, conjecture, and speculation seeping into some of the reviews that I wonder about the veracity of almost all of it.
For me, I go to Amazon quite a bit, as User reviews must have ownership, then I look for intel; both good and bad, and avoid those reviews that cannot seem to go much beyond 'Awesome' or 'Sucks'. So many folks get their feelings bruised over the slightest details, and I have little sympathy for many of them, as these issues have some of the easiest solutions.