Actually there is an anchor. It is not so tightly attached but it is there underlying U.S. Currency. It is U.S. Productivity.
It is changes in US productivity relative to other countries. If the country swings left it's value as a reserve currency declines.
Upoon close examination no support for this idea can be found. It is limited to a few cases cases. The broader picture suggests something quite different. The U.S. is the single most "right swinging" nation among all developed nations; yet their are several other nations to the "left" of the U.S. whose currencies are gradually sharing more and more of the role of reserve currencies.
It's funny to hear someone say with a straight face that the U.S. is going to lose it's status as reserve currency to the communist Chinese Yuan or socialist (in their minds borderline communist) Euro because....the U.S. is moving too far left! Charitably I don't think they grasp the concept that everything is relative in currency and they haven't moved to carefully consider the alternatives yet.
Nice try but your response was incorrect since you twisted my post to suit your bias. Countries that you have in mind are likely not swinging further to the left. As the US swings to the left and the left countries do not go further to the left the US loses gradually its role as the eminent reserve currency.
Is there any reasonable argument you can give to support your contention that gradual loss of the dollar's status as the reserve currency is related to the U.S. moving more to the political left? If so, state your argument. Otherwise I shall, and I suspect others will too, go on assuming your contention is nonsense and devoid of any logical basis.
Left bad, right good. That's going to be about the extent of any argument if you can call such simplistic reasoning an "argument".
Saying that if a contention ifs not proven is nonsense and devoid of any logical basis shows that you badly need to take a course in basic logical thinking.
It's the biggest economy in the world and can't come to an end that easily. Though there's a lot of fluctuations because of an increase in US Dollars supply during the pandemic, its role as a world reserve economy is still going to remain intact.