The above thread is only relevant to the built in deferred rendering path, not any SRP.
If you’re using the HDRP then the textures are going to be called _GBufferTexture0, _GBufferTexture1, etc. But I don’t know if it’s possible to access them from Shader Graph. It’s certainly not possible if you’re trying to access those textures from an opaque shader. You can try creating an unexposed texture property that has its reference name set to _GBufferTexture1 and sample that.