It's a good argument against trying sleeper/generation ships.
In practice, though, the actual sleepers would be so happy to arrive to find a nice McDonalds and a charming small town instead of shuttling down into the middle of uninhabited Arrakis with a 3D printer and a prayer.
Worse: your sleeper ship arrives at what should be a pristine planet. But FTL capable ships beat you there. And they ruined the planet over a few thousand years. And now they’re sending out refugee ships of their own.
There was a sci-novel about that, I don't remember who wrote it.
Essentially, after FTL got invented they caught up with generation ships and retro-fitted them with FTL drives; overall message of the story was that humans are a valuable resource and they should not be discarded lightly, especially in a mission to seed the galaxy.
It's a neat idea from a sci-fi perspective, but when you think about the most efficient forms of space propulsion (slingshots around large gravity wells) I'm not sure how we'll manage to do much better.
Either you catch up to someone before they leave the solar system or you're just going to shorten the time needed to reach their terminal velocity.
There's a diminishing return as you approach the speed of light, and FTL travel isn't exactly a trivial hurdle.