The company noticed that 1) folks were upgrading storage, and 2) hackers were adding pins so they could connect to the serial port. They then modified their production to include both of those hacks. They called it the "6416".
I've gone on to buy many of the GL.iNet devices. I take a Brume with me on travel. Their built-in software (OpenWRT with a custom WebGUI) is so handy that, despite knowing they have anti-features built in, I just use it as-is. I normally use it's 802.11ac radio to connect to the hotel, and copper Ethernet to my machine. But with dual antennas, you can also connect wirelessly without going half-duplex.
That DIY 6416? I use it as my home WAP, configured as a bridge to my central switch. It's been running 24/7 since 2015 or so.
GL.iNet also make an open-source hardware design. So if you're uber-paranoid, you can build your own.