Being that a Point is defined as the smallest effective military deployment, a Point of aerospace fighters or a Point of Elementals that do not act in concert for mutual benefit are only shooting themselves in the foot. Sure there might be a spirit of competition between Pointmates, but a Point that completely ignores its unity for the sake of individual glory is only going to reap quick destruction, so I don't think saying the Clans don't believe in he concept of wingmen is a valid statement.
The thing is: in every fiction depiction I have read from a Clan perspective of an Aerospace fighter: they do not think about
their wingman, they are focusing on what they, personally, are doing. Consider as well that the Clans deploy 2 ASF against
2 ASF, so that they each engage one fighter in a point. They might stick somewhat together, but they are certainly not doing
what the Inner Sphere would be doing of one lance(2 fighters) going in, and concentrating fire on one target, moving to support
and protect each other.
Personally, I attribute that to the fragility of Clan fighters compared to Inner Sphere fighters. The Clans know that one good
salvo will either kill or cripple most similar fighters to the one they are in, while the Inner Sphere know that most similar fighters
require a concentrated, and pro-longer period of damage to take down.
As we all know, Aerospace Superiority is the key to victory. The Clans could never achieve that, since they could not fight the
Inner Sphere pilots in the same tactical manner due to the way they have learned to fight from fighting other Clan Warriors and
the limitations of their equipment.