I have been an IT Manager and supporting technologies across different platforms sparingly for almost 20 years.
The curve is there, but you must provide training regardless of what you put in front of a user. Long gone are the days where you can just ride it out and stay with legacy technology. Think of UC, what a change, but people LOVE it now. MS Office (introducing the ribbon), people griped but now they fly around it like it's simple.
I will not debate the case that it doesn't take getting used to, that would be foolish. But I will say that for the average user, if properly deployed, and within a few minutes of navigation training, it's not a big deal.
If anything companies need to worry about users knowing too much because long gone are the days when you only worked on a work system at work. These systems are at home now and users will get their hands on them over the years and come back to the office and feel very comfortable (too comfortable) and misuse them as if it were their own personal home device.
If you deploy properly, even the training is curved, that is the purpose of a good managed environment, it is up to IT to make is easIER to use, intuitive and secure.
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