I was wonder why Anker new three in one cable has micro usb as the bottom cable and the lighting and usb c as the attachments. Wouldn’t it be easier to make either the lightning or usb c the base cable sine they are reversible and make the other two the attachments since then it doesn’t matter how they get out on. Maybe this is just me but I believe not having to worry about which way the attachments go on makes it a lot easier and mindless when using
I believe it comes down to reliability and availability and simplicity. Micro usb has 2 “hooks” which are designed a little bit better to lock devices into place than both lightning and usb C, making it a stronger joint. Another part is that with most electronics designs, its more reliable to split a signal from 1 voltage to 2 as opposed to joining 2 voltages to 1. The final reason which is probably the simplest reason is since USB-A is not reversible, its easiest to run straight lines to micro-usb, then put the splitting components in the adapters as Anker did.