Good point, but even SWIFT isn’t that important. The main source of the dollars power is that any currency other than the USD comes with a certain risk premium.
If you are a corporation that sells around the world, you don’t want to hang on to rupees, reals, or rubles.
If you have a billion in reals sitting on your books you either
1) accept the risk that they could drop by 10% next month
2) Pay $50 million a month for a currency hedge to cover that danger
3) Dump them for USD or Euros as soon as you can
Almost every corporation chooses option 3, and there isn’t much that could change that.
"...the dollar's share of global foreign-exchange reserves fell below 59 percent in the final quarter of last year, extending a two-decade decline, according to the IMF's Currency Composition of Official Foreign Exchange Reserves data. In an example of the broader shift in the composition of foreign exchange reserves, the Bank of Israel recently unveiled a new strategy for its more than $200 billion of reserves. Beginning this year, it will reduce the share of US dollars and increase the portfolio's allocations to the Australian dollar, Canadian dollar, Chinese renminbi and Japanese yen."
"Dollar Dominance and the Rise of Nontraditional Reserve Currencies" IMF June 1, 2022
Source: https://www.imf.org/en/Blogs/Articles/2022/06/01/blog-dollar-dominance-and-the-rise-of-nontraditional-reserve-currencies
I think that the West -- includes us and our USD and Euro accounts (I also at one time had a UK account when I worked there) -- have done a foolish thing with "economic sanctions." When a contract -- trade is about contracts and trust after all -- becomes voided by some sort of "confiscation," as various kinds of recent sanctions, but also a long history of the nationalization of assets by socialist policies, then trust drops. We are closing our Euro account as the signs of recession grow there, and we want use of our assets close to us (and dispersed across a number of institutions and real estate), even as a recession might come here.