Not just the District itself, but the Virginia and Maryland suburbs. I expect that a large majority of inauguration audiences are people who can easily day-trip. That fits fewer Republican voters than Democrats.
The pic the media floated initial, darling was not reality. The final crowd as seen in the other pics in this thread clearly show people filled up the lawn to the back after finally making it through a few security checks that had people standing in line for hours trying to get into the inauguration. So spare me the OP troll is going to get attacked for “facts” when it’s more propaganda.