I did a static analysis on their stock firmware this afternoon. There are 40+ binary blob at application level (excluding wireless drivers). I don't think there are any trade secrets there. It makes no sense to keep them closed source.
A lot of the closed source components contain Broadcom code that is labeled as Confidential by Broadcom themselves, and for which any redistribution is forbidden by their license.
There's also proprietary features such as AiCloud which Asus invested a lot of money to develop for their own products, and they are taking steps to prevent their competitors from reusing all of their investment, for free. Keep in mind that device manufacturers don't just sell hardware, they sell software and functionalities as well.
I'm surprised nobody raise their voice on ASUS GPL violation.
Because there isn't any that has been reported, and whenever an issue is reported to them, they promptly resolved it? For example, a few years ago, they made the robocfg source code closed. Since that tool was actually written by the open-source community (and it included code that I personally wrote as well), I pointed it out to them. They said it was a mistake (they assumed the switch-related code came from Broadcom's SDK - it didn't), and they reopened it in the following release.
Honestly, you are barking at the wrong tree. Of all the major router manufacturers, Asus is one of the most open-source friendly. Look at Netgear for example. Their entire firewall configuration, and their web server are both completely closed source, preventing developers like
@Voxel from even being able to modify it. He can't even add new pages to the webui due to how closed Netgear's code is. And when he tried to get in touch with Netgear to get their cooperation, they didn't just ignore him, but they started removing additional components from their GPL releases, making his job next to impossible.
So, I'm not sure why you seem to be on some kind of war path against Asus when I see far more flagrant issues with various competitors. For example, where is the Netduma OS source code (it's based on OpenWRT)? Or the SabaiOS source code (it's based off Tomato)?