It's a democratic Republic. We elect representative to make decisions for us, rather than meeting each day en masse to make decisions.

I don’t think you will find any disagreement on either point.

“Democracy” is often used as a general term for governments that in some sense are a delegation of citizen power. Even though a pure democracy would remove the delegation.

As a practical matter, the US model has devolved into a party-duocracy. Power at all levels has nearly completely centralized at the national level of each majority party. Of which there are only two. The extreme minimum of choice even for a Republic.

Incorrect, it was founded with more goals than that. It also has the mechanism of democracy for updating over time, and such updates have added prosperity producing things like taxation for public provision of education, infrastructure and much more. Which means that the initial version of the technology called the United States have long since gotten various updates.