WaPo doesn’t let me read the article — but a “green card” allows one to be a permanent resident in the USA. Something is missing.
Did he not renew it when required? Did he break a law which violated his residency permit?
Buried in the article...
Because Niec was convicted of two crimes involving “moral turpitude,” stemming from two separate incidents, he is subject to removal, immigration authorities wrote in the notice to appear, citing the Immigration and Nationality Act.
There are limits to it - look it up. It's not the same as being a US citizen.
He knew that he was only here on a green card. He had plenty of time to engage in the process to become a citizen. He used all that time to make a good life for himself. One would think that he would have enough gratitude to become a citizen of the country that gave him the opportunity to be successful.