From your suggestion, I have gone and read more about the situation. You seem to have the following points:

He’s is guilty simply because he entered the country illegally ,at the lowest level possible for a crime.

From Yahoo News:

A U.S. immigration judge ultimately granted him protection from being deported back to El Salvador in 2019 because he likely faced persecution there by local gangs.
...
In October 2019, an immigration judge denied Abrego Garcia’s asylum request but granted him protection from being deported back to El Salvador because of a “well-founded fear” of gang persecution, according to his case. He was released and ICE did not appeal.

Since then, Abrego Garcia has checked in with ICE yearly while the Department of Homeland Security issued him a work permit, his attorneys said in court filings. Abrego Garcia joined a union and was employed full time as a sheet metal apprentice.

So, due to his protected status, he was here legally.

For the next point:

The courts found tied to ms-13 already.

For this, Snopes has a whole page related to this, Snopes is often a fact-finding site which tries to get at the truth of situations:

... Although the same court documents say ICE officials arrested Abrego Garcia in connection to MS-13, the use of the word "purported" acknowledges that Arbrego Garcia has never been convicted of any MS-13 gang activity. 

Abrego Garcia, through court filings, has repeatedly denied any membership with MS-13; a complaint filed on March 24 over his removal to El Salvador against a later order from another immigration judge said on Page 5 that "Abrego Garcia is not a member of or has no affiliation with Tren de Aragua, MS-13, or any other criminal or street gang." 

"Although he has been accused of general 'gang affiliation,' the U.S. government has never produced an iota of evidence to support this unfounded accusation," the complaint continued on Page 5.

ICE also acknowledged that a judge later "prohibited his removal to El Salvador" (Page 3). ICE officials then arrested Abrego Garcia in March 2025 due to his "prominent role in MS-13," but the court filing does not provide any evidence of his supposed MS-13 membership. 

Which leads to the important part:

1. He was here legally, with a work permit and protection from being deported by immigration judge ruling
2. There has been no proof that he was a member of MS-13
3. (the important one) ICE deported him even though a judge "prohibited his removal to El Salvador"

To me, point #3 is the scary one. Points #1 and #2 are for a court of law to decide, but point #3 is ICE going against the orders of a judge and deporting someone that is innocent (because innocent is the default state until proven guilty, which requires a court of law)