Elon vs Kamala "Unelected Argument". What's the difference?

There was a lot of concern by the right that Kamala didn't win the primary, so therefore was not elected by the people to run for president. This was also the right's issue with the Chevron argument. That argument was that employees in the agencies were allowed to intrepret things based on their experience and knowledge. That was a problem because the people did not elect those workers and therefore were not the will of the people.

I'm confused in how that is any different than Elon Musk taking over a department and broadcasting demands to 3 million federal workers. The people did not elect him to run anything and yet here he is, bypassing Congress, using a budget for things it wasn't supposed to be used for. Didn't DOGE take over an IT Department? Did Congress aprove the money for this department to do the things it is doing?