Healthcare is only the thing that people most quip about.

Don't get me wrong, there are many good things about the US (e.g. networking opportunities, better availability of new tech, VC for startups, freedom to do things that just aren't possible in Europe), but OTOH, it's much harder to find safe walkable neighborhoods, excellent public transport, solidly built houses, and in San Francisco apparently human feces are a problem because of a homelessness crisis.