I work as a UX designer. I have to disagree with that claim.
There are always better ways to do things, but it takes time, feedback and experience. That is why we have updates and versions.
The assumption that more options equal more complexity is true to a degree and depends a lot on the design and architecture of the system.
In this particular case, the use of physical dials is a disadvantage for implementing quick functions that have dependencies on the dials settings.
Take the shutter speed issue that received a new implementation in FW4. That was an experience issue that got solved by implementing a dial override option.
A few months ago, if someone would have complained about this, he would probably get comments to either "don't use" that feature or "thank fuji for giving you that option".
And yet, Fuji came up with a solution that make the experience better.
I'm sure there are ways to ease some of the complication that came with the new AF features and one can start by giving clear indications on screen that some things don't work in the current camera settings.
I also think its good to let Fuji know about things we think can be improved (sound off-off = on) and don't assume every implementation is the best one.
There is always the next version... , or camera :-)
Cheers.
YC