The truck is not to tell them all the complicated shit. Just tell them it's another social media site that you browse. Don't need to tell them about the fediverse. Don't need to tell them it's independent. All that stuff is like a Naruto headband is to girls.
There is also an argument that there isn't even a need to advertise it... in fact some of the most popular things come from people "discovering it" themselves... and even then, some would argue they hope less people discover it yo keep their small town communities.