Maybe German and French politicians really are sufficiently pissed off not to want to negotiate. The referendum did have one important effect though: it smashed any illusions that Syriza is the problem. Heck, the No vote in the referendum was significantly larger than the vote for Syriza in the elections this year!
The problem is that the creditors insist on "squeezing blood from a stone", unwilling to reach an agreement that actually works, and the people of Greece insist that they won't accept that. Now, it's often said and true that in a democracy, the people of one country cannot be allowed to force their will onto the people of 18 other countries. But the facts are on the table; the Greeks have demonstrated that they won't budge. If the creditors won't budge either, it probably means total default and Grexit, something that ostensibly nobody wanted, but that is inevitable given how nobody was willing to make the necessary concessions to avoid it.
In the medium to long term, the Greeks will probably be better off outside a dysfunctional currency union, and the Euro will either get fixed or dissolved after the next few crises.