Why does the english rat defense scores so well for black?

if you compare this to to e4 d6 d4 e5 and the queens are traded, it is obvously inferior. The pawn on c4 is a better square for the bishop and black will just play c6 and kc7.

but there is the psychology of these positions. The right way to play this is to not exchange and black will transpose to an old indian defense most likely. To exchange is actual a self-selecting sample of people trying to stampede the position into a win thinking they have advantage. So, you have white trying to prove advantage in a dead-even endgame position black has likely played dozens of times and you new to it.

What awaits white is disaster.

This reminds me of the Philidor endgame. Or the ponziani/Philidor-ish endgame. Black has easier development and the black king isn’t that much of a liability as he can just move away if prompted. Whites pawn on c4 is also getting in the way of the white bishop

Now that I think about it. This endgame is quite equal and I don’t know why black has a much better score. But meh dunno 🤷‍♂️

This same motif happens in the Kings Indian defence.