He was the official sitting 46th US president when he wrote that letter addressing the nation "My fellow Americans" that he will step down from his official re-election campaign for official US president. Without any press-conferance or other official announcements. This is addressing highly official matters, not private, that effect national security. My point is it should have followed presidential communication protocols, that are in place for highly important reasons, including to make sure the president actully signed off on it. The people deserve proof of compos mentis.

Ok, but no. He was not resigning as President.