Ironically, I'm not as confident with my GX7's interface as my Olympus cameras' interfaces. It's purely down to how comfortable my own brain is with the two approaches, I think. It's not them, it's me!
I don't think this generalization is valid.
There are consumer electronics or computer programs/software that are easy to use, because everything seems logically and works as one would expect. This is not the case with the Oly menu system. One example is setting the size of the focus box:
On Panasonic (e.g. GH4), you can either go to the AF menu (dedicated button) and follow the on-screen instructions (pressing the down arrow) to get to the AF box size menu and resize using the control wheel or just tapping on the screen and see the same menu to move/resize the same AF box. There is no question mark in my mind when following this, it's a plain simple procedure.
On the E-M5II (or any other Olympus), I would also (following simple logic) go to the AF menu in the SCP, click on the Info button to change AF fields and ... that's it. I cannot change the size of the AF field here no matter what I do. All you can do is switch through the 4 different AF types. But you cannot modifiy or move the size of the AF box here in the actual AF menu.
To do this, Oly basically implemented a second AF menu (not accessible via the SCP), which can be accessed by touching the screen (if touch screen is enabled!). This will then bring up a totally different AF box which's size can now be changed, but not using the wheels but tapping on the on screen trackbar.
There is no relation between this and the first type of AF fields. They are two different things and I'm pretty sure this was done by SW developers who didn't want to extend the functionality of the standard AF at the time Oly implemented the first touch AF features but simply adding a second one, which is much easier to develop than providing a slick integrated menu for everything. Even worse, this mode will be lost on power on!
There are many other examples like this where all I can say is: WTF?!
And of course, with experience you can learn to live with all these things and it might become even normal for you, but I prefer not to have such a learning curve, just because somebody thought it was not required to simplify things for the user but simply pack in all the features and let the user get along with it (if he can).
I think it's time for a redesign of the Olympus menu!