That article joedirt posted doesn't even suggest Obam did anything wrong with documents. It quotes Julian Assange, of all people, as saying he heard "that destruction of records is occurring now in different parts of the Obama administration." Assign whatever sinister value you want to that bit of double hearsay from a highly questionable source, but also consider that the Presidential Record Act expressly assumes and allows outgoing administrations to "dispose of records that no longer have administrative, historical, informational, or evidentiary value." You don't have to keep the mountains of irrelevant documents generated over years in a bureaucracy with tens of thousands employees.
The current issue with Trump isn't that he destroyed documents, and his administration presumably did destroy thousands of documents when he left. It's that Trump appears to have deliberately TAKEN top secret, classified national defense documents with him, and without telling anyone who needed to know that he was doing so, and then storing them in unauthorized unsecured places. That's really dangerous, if true, and probably why its illegal. How does Trump attempt to fix that? By stonewalling attempts to retrieve the classified information and apparently lying about it all too. This current Trump situation is completely different than anything described in that irrelevant article posted by Joedirt, who probably just read the title and thought it looked like a decent prop for some low-grade whataboutyouism.