Exactly and that's why the US should be called a Constitutional Republic. At state level it's often much more democratic but federally, the US is not a (direct) democracy and shouldn't be called so by the media in matra-like manner. Watching CNN or MSNBC with bourbon shots on "democracy" is a drinking game that typically won't last the evening.

Electing or choosing leaders is how democratic systems have functioned, in one way or another, since the beginning of the concept.

Then it has never existed.

It is commonly recognized that Democracy could not exist at a granularity where everyone verifiably gets to contribute to every decision (even if only to abstain), including throughout the resolution of unsettled downstream decisions during implementation of settled upstream decisions.

This is very much not a surprise to anyone.

For any Democratic system to work, it must include systems of delegation.

One can usefully talk about tradeoffs of different kinds, granularity, processes and limits of delegation.

Is this democracy according to the math department? This does not conflict with the claim I made.