Death stranding's protagonist is a metaphor for The Artist. The Artist builds bridges, and in a sense Sam Porter is Kojima's self insert. He wants to bring people together again, and he does that via his art. Bringing us closer to one another through shared experience is the Artist's highest calling.
This game is incredible, but it's not gonna be for everyone.
EDIT to add: Notice how there are 'Knot Cities'? Sounds like 'not cities', right?
They're not cities, they're people brought together, strands that form a knot.
The Mayans told time and stories with knots. Knot calendars. Individual strands forming stories, knots.