The comet that was going to end the False Planet of the Saiyajins in M8 was capable of destroying an entire Solar System

[SIAD]

Paragus thought that Comet was going to destroy that Planet, even with Broly LSSJ. This was at least a little more powerful than Goku SSJ (Boo). Therefore Broly was not far from being a Solar System Destroyer.

  Will that Comet be able to Destroy an entire Solar System?

  The Comet that ended with the Dinasaurs had a power of 100 Teratoneladas of TNT. An attack that Raditz could destroy without major problems.

 

[Let's Go Fearless!]

Well the Saiyans can't breathe on space so that would ultimately kill Broly even if he survived from planet explosion.

 

[SIAD]

Well the Saiyans can't breathe on space so that would ultimately kill Broly even if he survived from planet explosion.

But could not someone destroy that Comet?

 

[Captain Cadaver]

Well the Saiyans can't breathe on space so that would ultimately kill Broly even if he survived from planet explosion.

Broly already showed the ability to shield both himself and Paragus in a Ki barrier when Freeza destroyed Planet Vegeta, so that wouldn't be the case.

Anyway, it makes little sense for the comet to be there as a plot device when you either have it being more dangerous than someone who can severely damage the South Galaxy, or just be a planetary threat that any of the active fighters could've dealt with easily. It's bad writing either way.

 

[Let's Go Fearless!]

Well the Saiyans can't breathe on space so that would ultimately kill Broly even if he survived from planet explosion.

Broly already showed the ability to shield both himself and Paragus in a Ki barrier when Freeza destroyed Planet Vegeta, so that wouldn't be the case.

Anyway, it makes little sense for the comet to be there as a plot device when you either have it being more dangerous than someone who can severely damage the South Galaxy, or just be a planetary threat that any of the active fighters could've dealt with easily. It's bad writing either way.

Well Paragus thought Broly would die along with others from the comet.

 

[Tapion]

Considering the comet in question was star-sized, destroying it during its coming would probably be just as bad as letting it hit the planet. The debris would undoubtedly hit New Vegeta and destroy it. And no one could intercept it from a safe distance via the spaceships, since none of them knew of the thing's existence until it was too late. All-in-all, I'd hardly call it bad writing.

 

[Captain Cadaver]

Didn't remember it being star-sized, so you've got a point there.
Not that it matters too much in Movie 8's quality when it already has enough contrivances and plot holes to make it far from well written, but at least that's not a real issue.

 

[Tapion]

Yeah, good ol' Movie 8 is crap. Nothing is gonna change that.