Bill Nye is a science "presenter". I think he was a mech eng at Boeing.

Degasse Tyson is a trained scientist but has a tendency to espouse opinions on subjects he's not an expert in, but with the authority of his professional background.

They both use the term Carl Sagan used. "Science communicator"

I'll be frank, if supposed "actual scientists" were better at science communication, may be there wouldn't be a need for "science communicators."

I say this as an actual scientist who mostly dislikes communication. I'm happy there are communicators out there that raise our profile a little, I don't feel jealous or spiteful for some reason towards them.

I think you're mistaking "communication" for "vulgarization". Most decent scientists are good at communicating their findings via publications. Making those findings understandable by laypeople, maybe not so much.

Your statement about Tyson implies that he isn't allowed to talk about anything other than the topic of his PhD defense.

No, that's not what I mean. Of course he like everyone else can have an opinion on anything they want to opine on.

What I'm saying is because of his background, that offers him imprimatur on things which he's not an expert but people will presume that because he's an expert elsewhere he's opinion in other areas are equally valid.