Welcome to games with increasing level caps. Gear gets outdated. Though I'd like to point out that so long as the daily, weekly or nightfall, or really any mission for that matter that isn't Croata's does not go above lvl 30 VoG gear is still relevant. You get no bonus for being over level of your enemies for either your character level or your weapons attack. So when you go on a vex mission you got the raid armour to help you. The exception I could agree to for this is any exotic equipment that a player gets. From the raid. (Not legendaries, sorry guys)