[RenderGraph] Wonder what the use of TransientTexture in raster renderpass

Am I correct the if transient texture is not set enablerandomwrite to true(which should be treated as normal attachment)in raster renderpass,then it is useless? I just cant figure out the usage the this transient texture as it only live in on graphpass, which means you can only set it as fragmentinput for reading or fragment for writting.I checkout the usage of this CreateTransientTexture method,and looks only HDRP use it in legacy rendergraph pass as an UAV.