Starlink will provide an immediate benefit to humanity, the astronomy performed otherwise, won't. Looking for exoplanets isn't a practical concern for humanity any time soon.
Then again, I am also not a fan of putting more satellites into orbit either... mostly just struck by your comment as being not terribly odd to me.
Travelling to exoplanets is not hard, it just takes 1000 - 10,000 years.
There will be no FTL untill we can manipulate black holes, if ever at all.
So the first trip to exoplanels will be in a multi-hundred year hybernation, or a genration ship, or people that are so different from us that they don't mind the journey.