I'm sure you can throw out statistics that prove otherwise, but I think the average living standard of Poland is already better than America. Again, anecdotally, but I'm American and I've lived in Poland for about a decade. Food, healthcare, housing, access to parks, public transport, etc. are all better quality here at the average-person level than most places the US.

Americans just end up paying for a lot of things that are either undesirable for many Poles (e.g., a huge McMansion in desolate suburbs and the car to drive there) or paid for via other means (e.g., healthcare.)

Which country has a better average living standard depends on if we are talking about mean, median, or mode. The American mean is higher and since most of the HN crowed works in higher-paying jobs in urban centers they tend to look at their own experiences to think that the US is a high standard of living country. If you look at the median or mode of living standards across a country then places like Europe are where you find more people experiencing a higher standard of living.

Oh, best of luck convincing Americans that paying twice as much for shitty health insurance than you pay in 'high' general tax levels is somehow a bad deal for them. Until they actually live the experience they just cannot comprehend the second and third order benefits of a real social system.