Recently there were two posts with more than valid arguments, but in the opposite direction.

In this post we can see how it is argued that Silver / Gold lobbies are more difficult than High Immortal / Diamond.

In this other post they convince us that the Silver / Gold players are not better that High Immortal / Diamond players.

From the following, we can infer that the Gold and Silver Players are exactly the same as High Immortal/ Diamonds.