People live longer in many parts of Europe than the USA. Does that mean the USA is somehow negligent?

Excess deaths due to heat are primarily the in the elderly. The excess numbers we are seeing now are because the proportion of elderly people in France, Germany and Spain are higher than in the USA.

If the population pyramid in the EU was more similar to that of the USA the number of excess deaths would be lower. I'm not sure negligent is the correct word to use. Climate change will reduce quality of life. Because of these changes people will not live as long.

That's how excess deaths work.