Three things worth thinking about in Chris's presentation:
First, the degree to which concern over the coin stems from the perception that it "illustrates the uncomfortable foundational reality of modern capitalism: Money is nothing more than a shared illusion." The optimistic way of framing that dimension of the opposition is that it's illogical and can be corrected with calm counter-argument. The more pessimistic take is that part of why modern capitalism works is that policymakers typically succeed in keeping the public from thinking too hard about how fiat currency is created.
Second, Chris argues that minting the coin would be simply part and parcel of an accelerating process of norm-breaking that's been happening throughout the U.S. government as Republicans develop new and more unprecedented ways to oppose this White House. Chris sees the coin as an overdue Democratic counterattack, while I worry more about the system's ability to withstand that much stress.
Third, Chris notes, rightly, that past periods of great strain in American life have often led to unsettling (at the time) innovations in currency policy. Abraham Lincoln printed greenbacks at a staggering rate during the Civil War. FDR took us off the gold standard during the Great Depression. Perhaps, when we look back, the platinum coin, or scrip, or the 14th Amendment (which I'm told is the preferred option of Senate Democrats) will be seen as another of these necessary innovations that helped the country survive the deep dysfunction taking hold in its political system.