I'll add in my $0.02. After having owned the HTC One (Google Edition and Standard), S4 and G2 I still think the HTC One is the better of all of them. It's just a more well-rounded product for me personally.
As far as the G2 and why I think it's not getting the love some think it deserves I can only wonder if it's the same reasons I don't think it's in the same league as a smartphone such as the HTC One: the G2 has zero personality and no identity of its own. Really, it just feels like a faster S4. It looks like a Samsung phone, feels like a Samsung phone and has features like a Samsung phone - both hardware and software. To some that's not necessarily a bad thing (depends on if you like Samsung and Touchwiz) - but to a critic that's a very negative thing for a product to not really have its own identity. An iPhone is an iPhone. HTC One is the king of material build quality in the Android world and has useful/fun features (front facing speakers, Zoe), Nokia's Windows Phone are unmistakably theirs, the S4 has a plethora of features/gimmicks and the G2 has... also a plethora of features/gimmicks. There's nothing that really separates it. Is it a bad phone? By no means. But is it unique and does it separate itself from other products? Only on paper, but not in day to day use.
The G2 doesn't really have any defining feature that truly sets it apart from the rest. By truly defining, I don't mean a 'unique' feature, I mean something that the average person can connect with and appreciate and its easily distinguishable. Instead, the G2 is a hardware guru's dream product, but really sort of falls short when it comes to being a unique product in terms of something exclusive. Sure, they have Knock On, but it doesn't always work right. Sure, there's the back buttons but that's really hit or miss depending on personal preference. Sure, there's the 24-bit audio (wired headphones only), but that means little to the average person who doesn't even know what that means, won't be able to tell the difference and needs an expensive headset to take advantage of it. And after that, it's just all copies/clones of S4 features that LG has tweaked with varying results.
The G2 is a better S4. It has a bigger screen, bigger battery, better processor... there's a lot of little things that are 'better'. But, put it side by side with an S4 and there are many average customers who would easily think it was a Samsung phone.
Finally, there's just way too much going on with the G2. I mean I thought the S4 was loaded up the **** with options. LG takes it to a whole new level. It's a cluster bomb of settings and options. So many in fact you'll miss many of them and not even know they are there.
Like I said, that isn't to say the G2 is a bad product, but it does explain why a critic would have a hard time with it. If LG came back next year with a G3 that redesigned their UX to not be so much of a Touchwiz clone you might see some better scores. Until then, it'll always play second fiddle to Samsung because LG is making it too obvious that they only care about beating Samsung by "being" Samsung.