That status is up for grabs no matter what he or any other US president does. If the current US government - Trump et al - succeeds in lowering the deficit and increasing US-based manufacturing - and those are two big ifs - there is some chance of the dollar remaining the semi-reliable (as in 'reliably depreciating') reserve currency it has been in the last 75 years. If they do not succeed the US will end up going bankrupt and will default on its debt payments which will spell the end of the dollar's hegemony. As to whether they can succeed in avoiding this without touching the sacred entitlement cows - Medicare, Medicaid et al - is doubtful. Many European countries have gone through years of austerity in attempts to come closer to the EU-mandated maximum deficits and I suspect the USA will have to go through a similar process. Even the cuts proposed by DOGE do not seem to fill the prospected gap between government income and spending.

I suspect they'll end up raising taxes on high earners but I also suspect this won't be enough since the entitlement programs are inflation-corrected and lack a backing fund. With the current demographical developments in the USA and the rest of the Western and Eastern world an ever shrinking working population will have to pay for an ever increasing non-working population. Since there is no backing fund - current payments are used to pay out current benefits - this system will crash sooner rather than later. If and when the dollar loses its status as international reserve currency the US government won't be able to simply 'print' more dollars to fill the gap and hyperinflation will soon follow.