Singling out a groups as scapegoats for all blame and the aspect of collective punishment

In line with many on the right, you are singling out Germany as a group as a scapegoat! Indeed Syriza's approach to the negotiations was to run a divide-and-conquer on the EU, trying to pit the rest of the EU against Germany. This backfired badly.

   Germany isn't paying for Greece

In what sense? Greece owes Germany €88.7 Billion.

    Sensible people trying to maximise the return on their loans would restructure them to take some loss but to enable Greece to recover to be able to pay the bulk of them.

Which is of course exactly what the troika is trying to do (however imperfectly), and much debt has already been written off or rolled over, but the Syriza government is blocking this as much as possible.

   there is something profoundly undemocratic 

Greece is perfectly free democratically to decide to ignore the troika, and default on all debt. Greece is also free to other other countries to pay for its debt, e.g. Japan, the US, Venezuela. But Greece has no unconditional right to other people's money. Why should Latvia and Lithuania, who are much poorer than Greece, finance a ridiculously bloated Greek military? There are much poorer countries still, Cambodia, Malawi, Niger, Angola. Why is it so vital that the rest of the world blows billions on fairly wealthy Greece, rather than these much more needy countries?