It’s definitely real, as it’s posted by a Microsoft developer:
We do have some feature updates in the works. One of the notable ones is a change we’re working on with Valve that’ll significantly reduce the amount of GPU memory used when running SteamVR. That one’s exciting because we’ve found it has a cascading effect - a lot of VR workloads tend to max out the GPU memory, and reducing the amount used reduces the need for memory paging, leading to a smoother overall experience.
This is probably only WMR-specific. Right now the issue is that we have to create an intermediate set of GPU buffers that we copy the SteamVR content into before we send it off to our system compositor. The change we’re working on will eliminate that set of intermediate buffers. Since each buffer is (generally) sized to match the resolution of the headset, the memory savings potential is huge.
The fix won’t affect performance that much, unless your current settings have you running out of VRAM:
It probably reduces the frame time slightly by removing that extra operation, but the copy shouldn’t be impacting performance that much. But at the same time reducing memory pressure can help a lot if stuff is getting paged out. We’ve definitely seen performance improvements in that scenario in our limited testing.