I guess it's to be expected that GL.iNet would focus on the latest products. However, the GL-AR300M looks ideal for 2.4G IoT applications. It's low power, so it can be powered by an always-on power bank like those from Voltaic Systems. A low-power repeater along with a low-power 4G LTE hotspot can be set up to provide good Wi-Fi coverage. I have a Blink Sync Module 2, Blink cameras, and a YoLink Hub in my IoT system. This system will function normally without AC power for more than half a day. This is completely separate from my multimedia Wi-Fi system.
I hope I can get support to solve the beacon loss issue on the GL-AR300M (I started a separate topic on this), so I can be confident of its reliability and suitability for IoT.