I got 100% world completion a few days ago. I had already gone into the Chantry of secrets a few points prior to the 100% (and did it again today just to be sure. It says 100% everywhere in game, on the map, on the char screen. I got the two gifts of exploration, the chest reward and the title. However I did NOT get a star next to my name.
And I haven’t done all of the explorer achievments either, so they aren’t needed for 100%. Im still missing a few areas on 3/5 main areas.