Honestly I think their description of its identifying characteristics shows that it is indeed pretty unique, and makes it fairly recognizable still when compared to their old logo:
Do you have an example of a rebranded icon that isn't too simplistic? And also doesn't look like it was design 15 years ago? This is an O that is also two moons, which I think is pretty damn cool.
You know they are supposed to be moons. If you don't know they are supposed to be moons, they could as easily get interpreted as some waves representing sound or something. I knew it was supposed to be moon-related due to familiarity with the previous logo and I thought at first it's a single one with some really weird shading. Next you're going to tell me these two moons are obviously going backwards. (Joke aimed at Rayman fans and people browsing my post history.)
The significant problem with saying an icon is too simplistic is that it's dependent on your market share. Google can get away with letters pretty much saying Google (that reduce to a big G that still has non-trivial coloring when appearing by itself) because it's Google. McDonald's huge yellow M is an old logo, but it wouldn't work with something of significantly smaller caliber. And, frankly, I don't care about things looking like they were done 15 years ago, IMHO it's often the simpler logo which looks like something done 50 years ago when manufacturing a lamp with arbitrary logo was too expensive and commie leaders didn't care, and it's a self-fulfilling argument anyway since you can exclude anything I like with it.
So Microsoft's new logo is a simplification of the previous iterations of Windows flag which is less imaginative but it isn't as pretentious because it's Microsoft we're talking about, and keeping it strictly on company logo level it replaces a cut within an O with an actual identifiable symbol (I doubt people consciously noticed the O cut and the font was more iconic to them). Bandai Namco's current logo is another example that adds imagery while doing away with recognizable typefaces. Ubisoft's latest thing is isn't more recognizable than the previous one, but it keeps the shape that is recognizable. Note, however, all of these are way more present everywhere than Insomniac.
If you look for something more in Insomniac's league, you have Sucker Punch, I guess. The redesign's alright. Not great, but alright. You will notice a lot of smaller entities did not rebrand too much in the first place, that's the big players' game in the first place. Even Naughty Dog sticked with their Crash era logo. Non-indie studio logos tend to stay static if these studios have logos at all.
The logic behind logo of Microsoft, Google, and Ubisoft simply does not apply to Insomniac. They're not the big fish that can get away with simple logos, or instant redesigns. The thing is, when I saw the Google logo redesign, I missed the old one, but I simply accepted quite fast that's the new one as I ended up seeing it, well, everywhere on Google's online premises and where they interfered, and I knew it would happen on that very moment. With Insomniac I see their logo so rarely that I will simply keep thinking about the old one, just as I do with Subway which I don't visit a lot. And their previous logo had that quirky atmosphere reminiscent of those games of theirs I'm associating them with. While this logo may have a lunar theme but the only sign it's not a law company or an IDE developer is that it says "games" in the corner.
They could have went in quirky direction of the old font, maybe fuse it with the contour, or keep something looking like a full moon with the rest of the new logo (which ties into insomnia theme while two moons... really don't?), doing away with both at once is overkill. I like the concepts posted above, though you lose on most advantages of the redesign in the first place unless you reduce the color count.