I guess it’s just the australian political landscape, which I don’t expect you to care about very much, suffice to say this guy is pretty far removed from the people who can actually make decisions or exert influence about who can be in Australia.
He’s a senator. No one in the senate has any formal interactions which the executive branch like immigration personnel.
He was part of a party called United Australia Party which was a far right protest party. I say was because he was the only candidate that got any traction and his party was disbanded.
He only got elected because he received a bunch of “preferences” from another party that didn’t quite get enough votes to win the seat.
All of this means that formally his only job is to make comments about proposed laws. He does vote on laws but he’s not part of a bloq so no one cares about his vote. Informally it means he doesn’t have any capital - he’s a barely tolerated pariah. Next election he will be lost to the passage of time.
His only play is to make headlines by making outlandish assertions, like “JB should be deported”, to increase his brand recognition when he inevitably retires from politics to pursue a lucrative career in financial planning or some such.