This is the baseless myth that won't die. We are nowhere near rivaling humans in mathematical proving. Even after a human has proved a theorem, it can be an astronomic amount of work to even explain the proof to a machine after the fact (i.e. to construct a machine-checkable version of the proof), even when using suites of sophisticated software tools developed solely to facilitate this process. Progress has been glacially slow since the field began in the 1950s. Deep learning has had zero impact.
We will have robots that can grasp competently way before we have machines that can rival humans in mathematical proving.