To my knowledge (and this is working off assumptions as well) Mercury, Io, Titan: Gone atm due to Pyramid Ships Mars: Chances are vanguard-wise they're unsure of what the Darkness did to the planet, so our exploration is limited Dreadnought: Likely no real reason anymore due to Oryx being gone, the Taken having taken new leadership, and our new alliance/armistice with the Cabal. So in reality nothing happening. Plaguelands: I think got soft retconned(?), but otherwise it was partially the cosmodrome, which was quarantined for a period of time likely due to remnants of SIVA. Likely specific teams went to deal with the remnants while we worked on other things. Tangled Shore: Spider left, and Mara reclaimed the area, so it's likely she doesn't want us interfering with whatever her plans are for the Shore. Chances are we're still allowed in the Dreaming City because it's still under the effects of Savathun's Curse. Venus: I believe has something to do with the Fallen there likely dissolving and splintering off elsewhere (likely with Dusk), and the Vex are seemingly more occupied with other locations now after the Vault of Glass (Black Garden, Nessus which is nearly fully terraformed, their giant portal on Europa). Lorewise, likely not much happening on Venus. If I missed somewhere let me know and I'll try to think through my knowledge on what happened to it, but that's why off my head.