I think a good way to look at soft power is it manifest through influencing people's decisions, whereas hard power manifest through the ability to make decision for others.
The collapse of American soft power will not directly lead to their overall collapse, fear can keep people in line so long as there is bread and circus, but losing soft power will effect people's choices, what product they buy, where they travel, what they invest in personally and professionally, what they study, and how much effort they put into everything they do. Globally it manifest when people choose a Chinese brand over and American brand, travel to China over travel to America, engage with Chinese businesses over the US, to buy Chinese USD bonds over T-bills.
Hard and soft power are interdependent and loss of soft power isn't a choice, it's a result of losing the hard power required to maintain it. Going all in on hard power is imperial self preservation instinct, like a body consuming itself when starving. America is like a person that has suffered a fatal dose of radiation, they're still alive, but their immune system has shut down and their cells have stopped dividing. They can still walk around for a while on what they have accumulated, but the death is already complete and it just takes a single traumatic hard power event to bring it down.
