Obama's EOs were a slow walk bureaucratic attempt, basically how you try to avoid actually doing something by making it easy to stymy. Same as Biden's broken promise on cancelling student debt. One stymied by the obvious avenues to do so, they can just sit back and let partisans repeat the excuses. They did not make real attempts to force the issue.

Here's a liberal-friendly summary that largely just repeats the words of federal and party bureaucrats: https://web.archive.org/web/20240902004637/https://www.newyorker.com/magazine/2016/08/01/why-obama-has-failed-to-close-guantanamo