Jason Ekstrand of Collabora just announced NVK, a brand new open source Mesa Vulkan driver for NVIDIA GPUs. No you're not dreaming but it's also not from NVIDIA directly — as usual the open source community is doing the work.
It's still early-ish days for NVK but what they've been able to do with it so far sounds reasonably promising. The current nouveau drivers for NVIDIA in Mesa aren't going to be removed but they don't exactly work well, and a lot of it was done coding in the dark with reverse engineering.
Things have come a long way though, with NVIDIA gradually releasing more documentation and recently their open source Linux GPU kernel modules.
NVK itself was written "almost entirely from scratch using the new official headers from NVIDIA" over the last several months targeting Turing+. Ekstrand has some pretty high goals for it, like wanting it to become "the new reference Vulkan driver within Mesa" and so they're "building NVK with all the best practices we've developed for Vulkan drivers over the last 7.5 years and trying to keep the code-base clean and well-organized".
This is a serious effort to get a good open source driver for NVIDIA GPUs and that sounds awesome. Eventually it could become "what RADV is to AMD hardware" but there's a lot of work to get there.
As for OpenGL support, they might even end up using the Zink driver (an OpenGL implementation on top of Vulkan), instead of writing a whole new OpenGL driver to go along with it. Zink has come a long way too so it could be a pretty good plan.
See the blog post for all the info.