This might not be a popular take here, but I think VR is going to expand pretty rapidly as the equipment gets cheaper/better. As of right now, Facebook and other large corps are trying to dominate that market with their "metaverse" garbage, so I think having an open source and federated VR network could be pretty important in the next few years. This is the only project I'm aware of currently that's trying to do that, and might be worth checking out: https://web.immers.space/

Aside from that, I federated social networks are important in general for freeing people from corporate control online, and there are a lot of projects to choose from there. I also think open source tools for DIY stuff could use more love, and open source CAD that could rival Autodesk/Solidworks stuff would be extremely useful for many people around the world. The realthunder FreeCAD branch has made a lot of progress recently and might be worth contributing to: https://github.com/realthunder/FreeCAD_assembly3