Because at that point the game's stage hasn't even been set yet, unveiling Sephiroth that soon without even knowing what kind of threat he poses is bad writing and counter intuitive to first establishing why he's even having those flashbacka to begin with.

That's why.

That soon? We don't know when that flashback occured.
It certainly didn't look like it was in the same room as the scene that came before it.

This appears to be on some street next to a concrete pillar. And it's unclear if this is where Cloud has the flashback, or if this is where the flashback itself took place.
Some details of Cloud's encounters with Sephiroth from Before Crisis and Crisis Core should be expected in this game.
Can also be:

Although keep in mind that this game is said to have extensive new content taking place in Midgar, that will flesh out characters like Biggs, Wedge, and Jesse, and let you visit all the different Sectors. So it would not necessarily be out of place to reveal a little bit more about Sephiroth at that point in the game, if we're going to spend that much more time in it.

You'ren looking at the point I'm trying to make. The point is that Sephiroth, for the sake of setting of the stage and putting importance of Sephiroth's/Clouds relationship into context - shouldn't be appearing in the game so soon regardless if it's the same scene or not. Sephiroth doesn't appear until you're a quarter through the game on the Junon Boat.

Why?

Because at that time, the stage had been set by the discovery of headless Jenova at Shinra HQ and Sephiroth's sword moments later. Which gave leeway to the importance of Clouds memory when they fill in the rest of the party (and the gamer) why Sephiroth being STILL alive is a big deal - despite Tifa and Cloud believing he had died years earlier.

THAT'S the point I'm trying to make...

Sephiroth doesn't appear that late in the game. His first appearance is in a flashback while Cloud tells the story of Nibelheim. This happens in the first town outside of Midgar, Kalm.

Right... I already clarified that much in the bolded characters. But let me make this SUPER specific so we don't all get hung up on small details.

What I meant to say, is that you don't meet Sephiroth in the flesh (so to speak) until the Junon Boat. I didn't use Kalm as an example because it's a flashback. I'm aware that the teaser trailer is insinuating it's also a flashback, but inserting a flashback at some point in Midgar is shitty writing - and does a piss poor job of setting the stage with Sephiroth as a character/villain.

You'ren looking at the point I'm trying to make. The point is that Sephiroth, for the sake of setting of the stage and putting importance of Sephiroth's/Clouds relationship into context - shouldn't be appearing in the game so soon regardless if it's the same scene or not. Sephiroth doesn't appear until you're a quarter through the game on the Junon Boat.

Why?

Because at that time, the stage had been set by the discovery of headless Jenova at Shinra HQ and Sephiroth's sword moments later. Which gave leeway to the importance of Clouds memory when they fill in the rest of the party (and the gamer) why Sephiroth being STILL alive is a big deal - despite Tifa and Cloud believing he had died years earlier.

THAT'S the point I'm trying to make...

Right... I already clarified that much in the bolded characters. But let me make this SUPER specific so we don't all get hung up on small details.

What I meant to say, is that you don't meet Sephiroth in the flesh (so to speak) until the Junon Boat. I didn't use Kalm as an example because it's a flashback. I'm aware that the teaser trailer is insinuating it's also a flashback, but inserting a flashback at some point in Midgar is shitty writing - and does a piss poor job of setting the stage with Sephiroth as a character/villain.

That animal game with the sugar glider looked very interesting, definitely something I'll be keeping an eye on! MediEvil releasing at Halloween is just perfect for it, and I'm SO FUCKING EXCITED!

... Final Fantasy VII Remake though; Oh damn! I wonder if we'll get a release date in June, but seeing more of it has just increased my hype even more, can't fucking wait!

Remember Wild?  

https://www.youtube.com/watch?v=JZwCLfTvmXo

Wild looks better and they are still working on it but in the end could be vaporware