While Obama made a spectacle of his vacation, he was as "away" as he was during his permanent presidential vacation. Which is to say that Obama doesn't work much, but he's always at the head of the projects of the left even when he's golfing.
While Obama was playing at being away from public life and on vacation, he was working to secure control of the DNC for his man, Perez, and his people were doing everything possible to undermine President Trump.
The "vacation" accomplished two things.
1. Obama is lazy. He loves to vacation on a constant basis. That doesn't mean that he isn't being briefed on the things he cares about and giving orders and setting matters into motion. Obama thinks of himself as an idea man, not a worker bee.
2. The stunt positions Obama's comeback. It also maintains the fiction that he refrained from attacking his successor and instead some time off from public life. And it attracts attention to his supposed return to public life.