But the latter moon landings were news items of the week. And the latter shuttle flights weren't even that, unless they were carrying interesting cargo.
The last human on the moon was almost 50 years ago. Shuttle flights (barring obvious exceptions) were pretty routine; definitely not the most inspiring missions. But humans back on the Moon, or on Mars, in the 21st century and setting up colonies? That's completely different proposition.
This is true, in the movie Apollo 13 it's portrayed as part of the plot that TV stations don't want to do a live broadcast of the mission. This is based on historical fact. Even Mission Control told them to cut it short because there was a Baseball game on. The broad public was only interested once something went wrong.