Having been following this thread from early on (and doing ethernet on an iPad in the pre-iPad Pro era), I've come to the conclusion that it's something that works well enough for some tasks, but isn't intended to be used for everyday purposes. In the earliest implementations, there were no settings for Ethernet (DHCP only), and we have the ability to see the IP address and statically assign things now. Still, I don't think it's a high priority for Apple to make this work beyond the bare minimum and I can't blame them. Most people (which is what they're targeting with these devices) are fine with Wi-Fi and would rather not having a cable hanging off their iPad. A handful of video chat apps are mentioned up the thread, but we're in a place where any sort of semi-competent Wi-Fi connection can handle those.
There are plenty of good and relevant uses for wired Ethernet, and I'm glad that iOS supports it (makes it easier for me to do troubleshooting for work off my phone). However, when it comes to most consumer devices, it's disappearing quickly.
You forgot to mention the fact that "the cable hanging off the iPAD" can only be there if it's charging the device.
In other words there's no way to use an Ethernet cable without charging the iPAD/iPhone battery. At least not with these new adapters. It's important to mention that because that also helps with using the device for a longer time, since we are stuck forever (at least that's what it seems) with this 10 hour (reduced over time thanks to battery degradation) on a single charge.
That can be a reason to justify using Ethernet even when wi-fi is available. I can't speak for others but I decided to
reduce EMF radiation, for example I don't leave the IPP 10.5 with wi-fi enabled even though I have a gigabit wi-fi router (Archer C8) close to me, and even bought a 2nd one (VR900) to use with my PC (which doesn't have wi-fi, only a bluetooth dongle). The alternative was to put a second ethernet cable, since I am moving the Archer from bedroom to another location.
If it was up to me I wouldn't use wi-fi at all. I also decided to sell my Airpods and recently bought new Sennheiser headphones and gone back to use the Earpods while they don't arrive. The thing is: there's no justification for Apple to implement Airplane Mode and warn us the app needs to connect - many times.
And there's no excuse too for apps start to break or don't work properly because Apple treats Ethernet as a "workaround" instead of a feature.
That's either sheer incompetence or done on purpose.
Here's what Apple needs to hear:
PLEASE STOP forcing users to do whatever you want, if I want to stop using BT headphones (not only due to EMF, also thanks to their battery that can't last more than a few hours) why would you remove the headphone jack?
Because in the future (or present) everyone is dumping wired headphones? That's a lie, it's just them pushing a new product and saying that's what we need, the same thing with wi-fi, if I want to use a normal cellphone instead of a smartphone (or a flip-phone) I can't anymore, if I want a wired (instead of a cordless DECT phone) these choices are removed from me.
Please, stop, just stop removing choices from the users. That's the only thing Apple does perfectly. It did recently by removing the Apple Store from iTunes (which was useful to backup apps, saving the .IPAs). For what reason? To remove junk from the software or feeding their megalomania?
You know what makes me sad? It's not that they do all these things or get behind jailbreaks.
It's the fact I seem to be the only person aware of how malevolent this company can be.
We live in a world filled with convenience and since we grew accustomed to swallow whatever is being imposed to us we never stopped to question anything. From now on I'll start boycotting devices and companies that do all these antics.
What is not a high priority for Apple is to do anything right. Whatever they do the fanboys will accept. That isn't working as it used to, tablet sales are plummeting since not everyone is willing to pay so much for so little.