No, it’s not the ‘fundamentals of football’.
It is a delicate balancing act - protect the near post (the most direct route to goal), but don’t leave too much space at the far post. As
@ValenciasDrilledCrosses has rightly pointed out, a keeper will rarely face criticism for faithfully protecting their near post, even if it is at the expense of their far post... seemingly this idea that you shouldn’t be beaten at your near post is a rather lazy cliche peddled mostly by non-keepers.
See the below quote from Kasper Schmeichel:
It’s a myth. Something I have never understood. One day someone just came up with it and said a goalkeeper should never be beaten at their near post.
Anyone who has played in goal knows it’s a huge area and you try to cover the whole goal. You can’t try and cover the whole goal and the guarantee the ball won’t go in at the near post if it’s a great shot. Near post, far post, you try to cover it all and you’re not happy if it goes in anywhere.
I’m not a keeper, mind, but that’s precisely why I don’t feel equipped to comment on the technical components of the role without having done some research myself. My conclusion is that I still don’t fecking know - but if top level keepers dispute the applicability of this myth, who am I to disagree? No one has said that a keeper shouldn’t protect their near post; rather,
people have questioned the assumption that a keeper is automatically at fault if their near post is beaten.
I can only assume you are a keeper given the confidence of your assertion.