The US absolutely needs more and better trains. But also, the US has large areas with no population. That's why when you look at electoral maps you need to control population density.

Even with a high quality rail system with support for populated areas of the US the map would still have large gaps and wouldn't be nearly as full as the EU map.

Simply putting two maps side by side and saying "this one bad" isn't great. Yes, it's absolutely bad, but for the exact reasons this map shows.