It's clear speculation, anyway.
The notion that - of itself - simplicity will win over complexity, is fundamentally flawed: a horse and cart is a lot less complex than a modern car; and an abacus much simpler than a laptop - yet look where we are.
MILC needs a USP far more compelling than "easier to make", and it currently doesn't have it.
It’s interesting though. When Apple came up with the Mac, people howled. Way back, I used to teach PC DOS part time, for fun. When macOS came out, people looked for the system config. files, and couldn’t find them. They would yell at how childish the computer was because they couldn’t edit them (while totally screwing up their machine, and calling me to fix it, but some people never learn). But the machine was even more complex. It hid it from the user though, which had it seeming to be simpler, and easier.
The thing is that these more modern cameras are much more complex in software and electronics. They’re even more complex than older, more mechanical models, but seem simpler. Apparent simplicity doesn’t mean operational simplicity, unfortunately, as computerized cameras, as we’ve found out, are ridiculously complex to understand, with far more “features” in the menus that most of us will ever need. Just because something can be done doesn’t mean it should be done.
Mirrorless isn’t simpler at all. It just shifts a necessary, though the lens optical viewing to an electronic, computerized one. The first camera from Canon doesnrvhave all the features of the 5Dmk IV, as some wanted, and expected, but that’s just a particular model version thing.