Is there any truth to the idea that European countries have better social safety nets and infrastructure because they are more ethnically homogenous?

Whenever I've talked to American voters, as an American myself, I'm it seems like there is an attitude of "that wouldn't work here" with regards to most policies implemented abroad. Including but not limited to a universal healthcare system (not even single-payer but even Beveridge Model or Bismarckian Model), fully subsidized college education, High Speed Rail, etc.

When I dig deeper the reasoning is usually something like "Well Norway, Sweden, and those other European countries are a lot more Ethnically Homogeneous so it's easier for them to make decisions and implement them." To me it feels like a cop out and a way to excuse poor public policy decisions here as well as in other "New World" countries, but at the same time I can't help but to notice that the countries that have done better at integrating immigrants (usually Anglophone countries), face a similar level of gridlock over implementing programs that'd benefit the many over the few.

What is your take?