It is just as cheap to put my R&D in Berlin as Greece (especially somewhere like Athens). It is cheaper to put my R&D in a place like Albania. Hybrid developed/developing is a great model, but you want your dev center to be cheap for opex, have a large number of skilled people available, probably a place where you have a personal connection, and such. University towns in the midwestern USA, Eastern Europe, Israel, India all make sense for people for that.

Greece has high unemployment, undeniably, but also has both high costs and high risk, and a really small technical workforce. That's not great for a startup.

I don't disagree that if I were Greek and in Greece, a startup would be a lot more attractive than remaining unemployed or trying to get a government job, but it's inaccurate and unhelpful to say Greece is objectively a good place to do startups vs. practically anywhere else. One of the keys to doing a startup successfully is to be honest with yourself about unpleasant things.