https://www.theatlantic.com/politics/archive/2024/07/biden-fades/678978/
This is about right on the NATO press conference. It was fine overall, however unfortunately that's not the standard that Biden has to overcome now. As Frum notes Biden gave detailed foreign policy responses. But as Frum notes there were the verbal stumbles (unfortunately right off the bat) and some half finished thoughts.
Perhaps most importantly: "Two very different things might have followed from that thought—but neither did. He might have tried to reassure his Democratic colleagues that he had some plan to turn things around, for him and for them. He did not do that, other than to vaguely suggest that things could be worse, the polls were not reliable, and other (unnamed) incumbent presidents had bounced back."
"If Biden loses to Trump, the nation Biden believed in does not outlive him. A different America replaces it, one where the presidency can be contested by violence, with judicially conferred immunity for an attempted seizure of power. Collective security will be junked, with American military power at risk of being hired by whichever dictators pay bribes to the president and his family."
From a rational standpoint Biden does still have a chance to win the election. Polling error exists and is relatively large. And the polling is still very close for a presidential election.
But we are in irrational territory. Dems are freaking out and they don't want to rely on a polling error.