Why is the Move 7...b7-b5 a good Move

This is the Game I played some Time ago and since then I Improved a lot but still don't fully grasp why 7...b7-b5! is a good Move.

Hopefully someone can help me out c:

In that position I dont see why that move would be good?

Are you familiar with Benoni (maybe even old Benoni) & Benko Gambit-

Zaitsev lines?

The positions (because of your early c5) are similar to those at times.

The problem here is both sides have ignored playing e4/e5 yet. More a problem for White because of the DSB not on d2.

You can gambit the c pawn (or also the a pawn depending on White's reaction) for play on the queenside (dark squares?). After White captures with Nxb5, just allows Ne4 (eyeing c3 square with the bishop and perhaps the Queen on a5) not Nh5 (that bishop is misplaced anyway). A Black knight on e4 can be a headache in many 1.d4 openings.

Trading knights & queens there might give White a hard time castling. Ba6 would be better after a5 (pushing that pawn always a threat).

Black has gain initiative and a very nice DSB

I play the Benko.  But i wouldn't play ...b5 with the knight on c3.

That's the thing about hybrid positions...you see the resemblances...you consider combining ideas.

I get that, and I didnt look at the position very deeply so i might be wrong in my assessment.   But like i said.  In that position, playing ...b5 just didnt seem like a good move.

I thought it was a strange one. Benoni was my first thought going through the game. Then being shown b5, reminded me of Benko.

Looking back at it before b5, Nh5 was my first thought.

Hopefully, we don't get in these types of positions too often. Earlier mistakes led to it.

There was a time i would have set that position up at home.  Busted out the pen and paper and dug in for some serious study, and analysis.  But now....Not gonna happen.

Where are the KID guys?

Looking for an improvement of .01 of a pawn on move 29...

In the actual game, visualize the position if Black played 8...Ne4 instead of  8...Ba6. Doesn't that look pretty nice for Black?  8.cxb5 a6 looks pretty active for Black too

Well, I did a little digging and this is a KID line. Different move order and not very popular. 11 or so games I found from 2015-2018

Ill be darned....and that is my interest and excitement level for this.

8.cxb5 a6 is the KID line I found (must be much better for White than the alternative)

8.Nxb5 Ne4 is what I was talking about...basic plans in a symmetric Benoni pawn structure. Not exactly what we have here, but it appears to be close enough. Might be a KID opening, but the pawn structure isn't...at least not that I know of (a few variations exist).