The program’s end
The act specifies that for a former president to be honored, they must have been
deceased for at least two years before issue.[26][27] Hence, former presidents
Jimmy Carter, George H. W. Bush (now deceased), Bill Clinton, George W. Bush,
Barack Obama, and current President Donald Trump were ineligible to have a
dollar coin issued in their honor. The series ended in 2016, after honoring Ronald
Reagan, the last President who was eligible.
Since the program has terminated, producing coins for those presidents not yet
honored would require another Act of Congress.[28]
https://en.wikipedia.org/wiki/Presidential_$1_Coin_Program
Stockpile and suspension of production
By 2011, 1.4 billion uncirculated $1 coins were stockpiled,[21] which, if stacked flat,
could reach from Los Angeles to Chicago. By 2016, this number might have reached two billion.[22]
Rep. Jackie Speier of California circulated a “Dear Colleague” letter recommending
that the U.S. not produce any dollar coins. She was planning to introduce legislation
calling for the immediate halting of all dollar coin programs.[23]
The United States Government Accountability Office has stated that discontinuing the
dollar bill in favor of the dollar coin would save the U.S. government about $5.5
billion over 30 years.[24]
On December 13, 2011, Vice President Joe Biden and Treasury Secretary Timothy Geithner
announced that the minting of Presidential $1 coins for circulation would be
suspended.[21] Future entries in the program, beginning with those of Chester A. Arthur,
would be issued in reduced quantities, only for collectors.[25]
https://en.wikipedia.org/wiki/Presidential_$1_Coin_Program