crew reported smoke in the cockpit, stating a bit later that the smoke had cleared
I think you will find the Land at Nearest Available Airport only applies to "Cabin or Cockpit fire/smoke that persists" quoted from QRH
Bit early to be making judgements, could have been a simple window heat arcing creating the smoke/crew dealt with it, no reason to land at nearest Airport. Not saying that was the cause, have no idea, but it's a bit rich to be making judgements with the tiny piece of information at hand.