Stone wasn't pardoned. His sentence was commuted. He is still guilty and convicted of his crimes, he just won't be serving any prison time. Given his age and such, that's probably a good thing for taxpayers who would otherwise have to pick up the tab for his medical care. On top of that, the federal prison system has a mechanism in place for inmates of advanced age, like Stone, to be released on humanitarian reasons of infirmity and advanced age.
https://www.pagepate.com/what-is-the-compassionate-release-program-at-the-bureau-of-prisons/
So, the Stone commutation is a NOTHING BURGER!