It's the person behind the camera... Higher specs and higher quality video, doesn't mean anything, if the person operating it is a beginner.
What really sets the two apart, is being able to shoot in a flat profile, increasing detail you can bring out in post. And being able to expose properly in camera, which is a time saver, not something that's impossible to achieve with a phone. If you do it with a phone then you'll have to track masks, which takes a long time.
If you expose correctly with a DSLR, you remove that step, unless you're correcting a mistake, or going for a VFX shot. You only have to color correct, then color grade, which speeds up workflow.
It's a convenience thing, phone video can't compete when it comes to a fast workflow. But in editing programs, you can change alot of things, even make it look like a professional video, it just takes longer to achieve the same result.