rereading old Jammer/St-Hypertext review’s of Extinction, harsher than I remember. I was more entertained by this silly episode than others even if we quickly disposed of the Xindi arc this ep in favour of an alien of the week episode 

He’s right that this is a recycled Voyager plot, and we don’t even bother to ask this seemingly organized civilization quarantining the planet anything about the Xindi.

It doesn’t fare much better behind the scenes either, via Memory-Alpha:

• According to Trekweb, LeVar Burton went to the producers and told them he was “ashamed” that he had directed this episode.
• Ten years after this episode aired, Brannon Braga called “Extinction” “one of the singularly most embarrassing episodes of Star Trek I’ve ever been involved with.” (“In a Time of War, Part Three”, ENT Season 3 Blu-ray special features)