The Jets haven't released Eric Decker yet as they are still holding out some hope of being able to get something for him:
Per sources, Jets have had trade talks with the Ravens and others on Eric Decker. Decker remains on the Jets roster, per the league wire.— Albert Breer (@AlbertBreer) June 8, 2017
The Ravens are well aware that Decker will be released if the Jets can't trade him, but if they are aware other teams are interested in him then they might not want to risk losing out to a team with a higher waiver priority.
Even so, the best the Jets can probably hope to get for him is a late-round or conditional pick - or perhaps a veteran player that was a candidate to be cut or has a salary that the Ravens want to dump.
It makes no difference from a cap perspective as to whether Decker is cut or traded, so this is basically just a situation where the Jets will hope to receive an asset in return for him. Ordinarily it could also be to perhaps have some control over where he does (or doesn't) go, but that's probably not much of a priority this year with the team not expected to contend.
The one transaction made today saw Quinton Patton released off injured reserve with an injury settlement. Given the severity of his injury, it's likely he received a payment of most - or maybe all - of his salary and would not be able to return to the team this season. That money does count against the cap and Patton already didn't count against the roster limit, so the Jets still have one open spot following David Harris' release earlier this week.