Windows 8 is different (8.1 not so different from 8, though), but in my opinion as a computer professional since the '60s who started out on Multics, and then became lead Unix administrator for a major Federal agency renowned for its technological prowess, it is better, an improvement in logic and usability on top of its improvements in efficiency, stability and security. Furthermore, it takes less space on the hard drive, boots faster, and everything runs more crisply.
But there is indeed a learning curve (albeit not a particularly steep one) because many of the things that you knew have moved. They're all still there, but not where you had become accustomed over the years to finding them. Obviously, chief among these is the "Start Menu," but third-party freeware applications emulating it are widely available if you really need it. It really is unnecessary, though.
But the thing is, its functionality is all right there and readily accessible, where it should have been from the start had computers in the mid-'80s been capable of doing it that way. Someone just starting out now on computers will find Windows 8.1 far easier and quicker to grow comfortable with than the O/Ses, even the 2.03 through 7 versions of Windows (which all maintained a similar user interface and underlying UI logic) were when we first sat down at a Windows-computer keyboard.
Now note that I do not use the Metro UI ("Start Screen") except whwen the computer boots up. I configured it to display the apps I want to use first in the day, click once on it, and it comes up in my good old comfy Desktop, which remains there for the rest of the day. It is actually a labor-saver (although rather minor in that regard) in that I need only click once on the first app of the day instead of the twice I had to click on it previously.
The Desktop seems to me to be pretty darn close to what a "Windows 7 shell" might be.
Of course, I have icons on my desktop for Computer, Control Panel, Network and Command prompt, but I always have, and I have never understood why other people so often didn't put these on their desktops. It makes everything so much easier.
There are always those who are thrown for a loop by something new. Some people grouse about it loudly and publicly (Vista particularly suffered from this effect -- it was a major improvement that got badly and wrongly slandered by self-styled "gurus" whose shallow understanding resulted in the change costing them their guru status in the eyes of others, and they resented it). People resist change whether for the better or not, but Windows 8 was a change for the better and 8.1 is an improvement on that.
My suggestion to you is to keep using it until you grow comfy with it. You will. It really is an improvement and everything really does make more intuitive sense once your "muscle memories" of XP fall away.