Raspberry Pi Guide Pinout confusion

The Archive Raspberry Pi
3

I’m not sure what the issue is. The documentation you link to is accurate.

This codes makes the green status LED of a Raspberry Pi 3 blink for me.

void setup() {
  pinMode(D7, OUTPUT);
}
void loop() {
  digitalWrite(D7, HIGH);
  delay(1000);
  digitalWrite(D7, LOW);
  delay(1000);
}

With the same T-Cobbler Plus as in your picture, with the same cable orientation and a Raspberry Pi 3, this program makes the pin labeled #4 toggle.

void setup() {
  pinMode(D7, OUTPUT);
}
void loop() {
  digitalWrite(D7, HIGH);
  delay(1000);
  digitalWrite(D7, LOW);
  delay(1000);
}