Your "facts" are "as described by the convicted criminal" and they are minimised. What you believe is heavily influenced by your desire to put a gloss on Trump's actions.
Other than "she didn't meet all the criteria" I can't find why she was not given clemency under Obama when thousands were (and you didn't stop to ask). Maybe she should have been and I am not defending the sentencing policy of the USA.
But that is the issue. Obama set up a system to look at cases using set criteria. Trump intervened personally on the sole criterion that a political ally asked him to, but is leaving thousands more to rot in prison (you've highlighted Johnson's own words on that).
She was a first-time offender but had committed thousands of offences before being caught. And as for her offences being non-violent, here's Trump's view: “If you shoot one person, they give you life, they give you the death penalty. These [drug dealers] can kill 2,000, 3,000 people, and nothing happens to them.”
Johnson was convicted for being the leader in an operation distributing two to three tons of cocaine.
https://www.vox.com/platform/amp/policy-and-politics/2018/6/6/17434760/trump-alice-johnson-pardon-kim-kardashian