Interestingly, the function names are exactly the same - I guess people think similarly :-)
It looks like append() also accepts strings directly. This eliminates the need for $T, which makes things even nicer.
The small bytes also mean that for simple sites I can just copy paste it before transitioning to a real setup.
You’re not wrong about clarity; it wouldn’t hurt here at all, but it wouldn’t hinder without, so I imagine it’s to reduce cognitive load and make it abundantly clear the function is logicless glue.