Good video. It's good you're honest about your experience. Finns have somewhat ambiguous feelings about their country being measured as the happiest one; mix of pride and scepticism. I'd say that in FInland "contentment" is a better word than "happiness". Someone has put it this way: Finland isn't the happiest country, but the least unhappy one. An overt expression of happiness in Finland is considered gauche, unless it's related to sports. To give space is polite. You talk when you have something meaningful to say. Small talk doesn't really exist. Initial impression for people unaccustomed to Finland is of somewhat melancholic people living in a cold but reasonably well functioning society.
Sorry, but there is certainly no official day of failure in Finland, this must be some sort of joke campaign you have taken for fact. History for 13th as unlucky number comes from Bible and history. On Friday, October 13, 1307, King Philip IV of France ordered the arrest of hundreds of Templars. What comes to food and weather: your portions look disgusting. There are plenty of good quality restaurants close to Kauppatori, even ones with Michelin stars. And thanks to global climate warming we suffer nowadays from high temperatures as well. And yes, in general we are beeing less reactive and hysteric after incidenses like the car crash you described. This is just outwards behaviour though, reminds the japanese culture in that aspect.