That statement is true. Along with all full backs attack. However there is a distinct difference in how that is implemented. Our focus is to track back first.
It is a distinct difference.
Our default defensive position - not in possession - is (has been at least) to sit really low with our back four. Mourinho-style. Not to get countered and fall back first instead of press the ball.
He has always played like this. It has its advantages, it pretty much eliminates the opposition´s possibilities to attack the space behind the defensive line and the GK Which is a dangerous space, maybe the most dangerous.
To that to be true though; it requires the back four to play extremely narrow to eliminate the area between CB and FB. A space that is as much or more dangerous if you defend low.
An area that "modern" teams like Barca and City thrive on exploiting. Because if they do manage to exploit that space against a opposition sitting low they are in on goal. We see this a lot especially with Guardiolas teams.
They dont really need a physical presence up front because any "crosses"will come from inside or just outside of the penalty area. Low and hard.
Back to Mourinho: Having to play a extremely narrow back-four, because of sitting low to begin with results in someone to handle the channels though: which in a Mourinho/defensive system leaves the wingers.
When we play a possession-oriented team that dares to push their FBs up in possession it results in us playing a 6-3-1. A player like Fred has no place in such a system (to keep this rant thread-oriented).
I never wanted Mourinho to begin with, which this post might reveal. That said, his type of football can work. But if we are supposed to keep playing like this, we need a new #9 to begin with. We cannot play defensive counterattacking football without a real target-man up front. IMO.
End rant.