Define "most people who have weighed in on it"... because I doubt you have any data to back up that statement.
And define "overly difficult to use". What exactly is difficult? Being a jarring or unexpected visual is not "difficult to use". You tap the windows key and type to find things. You tap the windows key and click on an app to start it. You scroll left and right. I'm still trying to fathom what you find "difficult" in any of this.
It's DIFFERENT. And yes, if you try to do things the exact same way on a system that is different, you're going to be frustrated and angry. But that's not a problem with the system, necessarily.
But all the functionality is there, and the vast majority of it is available to you in the same, or fewer, keystrokes and/or clicks. A FEW things are not optimized, and a very FEW things aren't present or require a different strategy with this pre-release, non-final UI. There are also several things you can do now that you couldn't do before.
Any time anything changes, there is always this HUGE outcry. Usually it settles down once people wrap their heads around the changes and realise they're not nearly as horrible as they initially thought they were. If only people were more constructive in their feedback, rather than just "THIS SUCKS I'M NOT USING IT"... everything would be better.