This is going to be part of the default package soon, which is why we have not automated this step yet: nvidia-utils: Enable PreserveVideoMemoryAllocations and TemporaryFilePath (55644f78) · Commits · Arch Linux / Packaging / Packages / nvidia-utils · GitLab
And just to note, we NEVER recommend using nvidia-all. That package does not update along with the rest of the system and should be avoided at all cost.