XCOM: UFO Defense was made in 1993. I was in college then, and I played like a bunch of different PC games then. Nearly all of them had manuals, and required you to read the manuals before you played the game. Remember Elite? That game gave you a 200 page instruction manual and there was no way in the world you could play the game to its fullest without the manual. Same with Masters of Orion (made by Microprose, the original developers of XCOM) - you had to read the manual. Microprose/Atari intended the player to read the manual for XCOM. And most of us did.
The reason we had such huge manuals and very few tutorials in games then was because we had limited memory and disc space. Everything was on floppy disc. XCOM: UFO Defender came out on 5 1/4 floppy discs, and required a tiny bit of memory space. Not having a tutorial helping you is not a feature of XCOM - it was a limitation. And they fixed that limitation by giving you a manual to read to fill in the gaps.
We had the equivilent of a tutorial in the late 80's and early 90's - it was called the Manual. Your expectation that an XCOM remake shouldn't have a tutorial to help the players start the game and just throw them in there is unfounded. Because it was a great thing for you didn't mean that it was a great thing for a lot of fans - a lot of us who read the manual liked it because it was a good game period. If you want to experience the way you played it the first time, then shut the tutorial off. LOL"
I learned early on from Microprose that you must RTFM on these games. Masters of Orion taught me that instantly since there's so much you miss if you don't read the manual. Since the tutorial or opening was not very informative in its own. I gather you didn't read the manual for XCOM: UFO Defense or you skimmed it at best. To me it was never "broken."
I think what made XCOM: UFO Defense a superior tactical/strategical game was that it challenged you, even when you were reaching the pinnacle of your research and troops. Even if you had all the tools, the game swarmed you with invasions. Not the lack of information that was right there in the manual if you took the time to read it. I'd prefer a five minute tutorial to the game over a 134 page manual any day, though.
If Firaxis keeps the difficulty and the spirit of the game, that's a win for all of us who have been waiting years for a proper remake of XCOM (not some fan-made rip that seems to fall flat)."

This is Sid Meier's company. Fraxis is good at creating both simulations (Gettysburg and Civilization) and narratives that have doom looming on the horizon (Alpha Centauri is the best at demonstrating that). XCOM was both types of game - a simulation and a narrative of imminent doom from an alien invasion. I think they can do it, and I think they won't hold back the punches from the original game."