Now, I could be wrong, but I don't think half these countries are signatories to the NATO accord.
Most of the nations charted did not commit troops to combat in Southern Afghanistan. They pretty much stayed out of the fight and took far fewer casualties than the main participants.
Who were the main participants that helped the US when called? The usual suspects of the Anglosphere. UK, Canadian, and Australian special forces were dispatched in 2001.
From Wiki: "Approximately 40 Joint Task Force 2 (JTF2) assaulters were sent to southern Afghanistan in early December 2001, although the Canadian public was not informed of the deployment, following the American declaration of a War on Terror.... in Sean M. Maloney's book Enduring the Freedom, it was reported that JTF2 was secretly deployed without Prime Minister Jean Chrétien's permission in early October 2001.[1] (In October 2004, these JTF2 personnel were awarded the US Navy Presidential Unit Citation as part of Task Force K-Bar, a multinational special-operations task force led by the US Navy SEALs that was decorated for its operations during the period 17 October 2001 through 30 March 2002.)"
According to this, Canada sent special forces within a few weeks of 9/11.
When did the Germans, for example, go in, and where did they fight?
Know who your real friends are. Hint: they speak English, they fight and they take casualties to defend western civilization.
Back up a little. You wrote, “That said, I didn’t notice all the other NATO nations rushing to help the US in Afghanistan.” I noticed.