Battle Garegga at #1 is also suspicious. It seems that some people vote for it out of "respect" because they're "supposed to". The game's not even close to as complicated as people make it out to be.
Eventhough I actually love Garegga and would put it in first place any time, I can see your point and agree on this one. Stuff that baffles me though: Why should an especially complicated game be in first place? That point doesn't even come close to qualify a good game.
And then again, can there be an actual first place where your statement doesn't fit? Every possible game that can be in first place can possibly be overrated because people "are casual", people "respect it 'cause they're supposed to be" or people "just feel obligated to vote for it".
So while I can see your point, it's not very strong with the arguments you gave and easily interchangeable depending on which game is at first place (With the obvious exception of some game you really like. Would you say the same about Fairy Wars?).
So what the fuck is actually being suspicious
I think Garegga very exceptional, People just tend to overcomplicate it a bit, it was a separate point from the one voting out of obligation. I've concluded that these points are true in some regard by browsing the forum, but of course, part of it is speculation too. I think it goes hand in hand with the problem of voting for a game you think is "great" but you "don't like/don't get". If you look at the top games then Garegga pretty out of place and I just can't help but question whether or not everyone that voted for it actually likes it.
As far as complexity is concerned, people tend to focus too much on the surface, when I think what matters more is how complicated is the routing, dynamic decision making, possibilities, and so on. This isn't something you can just easily measure but I personally don't think Garegga should be put on some sort of pedestal and that Ketsui for example has at least as much depth, yet that game is known for having a pretty simple to understand system so it gets taken more for granted. Just an observation. I can't agree that you could say the same things about any other game. Most games aren't discussed nearly as much as Garegga in the first place. Cave games are taken way more for granted, and any other developer just isn't popular enough.
So yeah, when I said suspicious, that is because I'm honestly questioning whether many people even "know" the game they're voting for, and if they like it.