Why do we keep losing against the London System ?

It's actually simple.
Yossif Dorfman explained in his book The Method that there are at least two types of advantages: dynamic advantages and static advantages.
The London System controls the e5-square from move 2 thanks to the d4-pawn and the bishop on f4.
That's a static (and long-term) advantage, which can be turned into a more dynamic position once White groups the knights towards the e5-square.

Since it's so simple, why do people not avoid it?

In most cases, players with the black pieces are missing a key aspect: they never fight for the e5-square directly.
The engines might agree with most of the lines that don't fight directly for the e5-square, but in practice the positions can get out of hand very quickly.

That's the point of this article.
Let me show you a human-like way to play effectively against the London System.

Get access to the complete study + bonus by joining it here :
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Thank you for reading this article. If you want some newer lines and analysis, I invite you to watch the YouTube video that I recorded for the occasion.

https://youtu.be/rvAP_F9PBXo

Thank you,
Loris