Why is d5 a good move here?

The computer recommends d5 multiple times, but I had rejected it earlier because I felt that it blocked my bishop on c4 and took away the hole in d5 rendering it unusable. Can somebody please help me and tell me why it’s a good move? Thanks!

@CalbernandHowbe I think the computer recommends that move because it makes black retreat his knight and bishop and then you would have more space than your opponent.

True, I would have more space but wouldn’t my bishop be bad as the d5 pawn blocks it and my knights as well as there are no squares for them? Thanks for your answer though!

possibly after d5 na4 bb5+ Bd7 Qa4 forces the black king to move

Not Bb5+ Qa4+ is winning knight after Na5

@ReallyWayTooBad after d5 the computer recommends nce7 bb5 bd7 bxd7 qxd7 not na4 be2 when I am much better apparently. After the first line then I do see that I have a big space advantage, so I do kind of get that.....

@Fullbasket qa4 does not win the knight, the queen is protecting it so just bd7 after bb5

I don’t really know but your bishop can go to b5 after d5 and then qe2 maybe. Also, for your b1 knight it can go to c4 and attack blacks d6 pawn.

Thank you all for your answers this is helping

@CalbernandHowbe id say it's because he should play Ne7 then you play Bb5 and he has to block with bishop d7. Then you can trade and play c4, you have a big space advantage later you can prepare b4 and try to destroy his queenside. So black has to get counterplay with f5, so it's some Kingsindian like position but you got his white squared bishop which is a big advantage in these positions because white might get a knight to e6 if black plays the attack too quickly so he should play h6 first that delayes his attack and every tempo counts. Also in some position you can try to blockade his attack for example if he get f4 and g3 in u might play h3 but that wouldn't be possible if he had a white colored bishop because he would play Qh4 and take on h3. That would be my point. Nevertheless I can't dislike your move Qb3 it's a very normal good move.

@hirnloserverlierer

Thank you so much this helps a lot.