“Certainly when you look at foreign holding of USD long term assets that amount is going up quite fast as well…”

Agree. Gemini backs what I’ve heard:

“T-bills (Treasury bills) are currently experiencing exceptionally high popularity and robust demand in recent auctions, characterized by record-setting, oversubscribed, and large-scale sales.”

Buffett himself in recent years thought there was no real concern wrt dollar being the reserve currency for the foreseeable future.

“Warren Buffett maintains that the U.S. dollar will remain the world's primary reserve currency for the foreseeable future, seeing no viable alternatives. While recognizing risks from excessive money printing and potential "de-dollarization" trends, he believes the dollar's dominance is secure due to a lack of better options.”