Well just for example, if someone was going to remove their front pump by threading bolts into and up against the machine gasket surface, this would burr up and score the machined surface. I would call that wrong.
But if a guy knows to use a couple of slide hammers to pull the pump, all is good imho,
But so is two pieces of threaded rod and a 2x4 with a hammer. To me that is not wrong.
Not everyone has to own the latest snap on tool to do the same thing. Imho
But I have also seen experience builders on YouTube knock the pump out from inside the case with a rod, probably to save time.
Probably ok for a very experienced builder who knows what to watch out for like Cudaback mentioned, but perhaps that would not be the way to teach a newby on his very first rebuild.