39 billion is inconsequential to the U.S. economy considering how recklessly the U.S. government will spend trillions of dollars without thought, and subject them to exponential debt growth. Besides, they've sent Ukraine more than that in aid over the past year.
This is nothing more than a campaign tactic for Biden seeing as it's election time. The Supreme Court struck down his insane proposal of forgiving nearly 500B USD in student loans which would have allowed him to spend an unforeseen amount of money and circumvent Congressional oversight simultaneously. Not clear how he has the authority to forgive 39 billion -- assuming it's through executive action, all he did was essentially print 39 billion USD into the economy. Consider it an expensive campaign expenditure.
You do understand that money most likely stays in US and acting as a stimulus package and those people have now more to spend in US products, and that's indirectly driving economy up.
And US has insanely big budget anyway and this is like fraction of a drop in a sea. From outside looking in their taxation doesn't make any sense. They really should tax the rich more for the system to be sustainable.