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View submission: How do we know what exoplanets look like?
While this is correct for distant objects like galaxies and some stars, it is extremely unlikely for exoplanets. There are only a handful of reasons why an exoplanet would die out, with those being either the host star dies and kills off the planet, or the planet is in a dynamically unstable orbit (either naturally or through interaction) and either gets removed from the system or destroyed.
The furthest known exoplanets are still within 30000 light years from Earth, meaning that at most we are seeing 30000 years into their past. This is an eyeblink in astronomical timescales. Unless the host star already appears to be in it's final stages of life, it will not die off in that timeframe. Of the 5000+ exoplanets we have currently confirmed, only about ~150 of them orbit red giant stars (https://arxiv.org/abs/2001.00050[1][2]), so the chances of one of those dying out is relatively small.
1: https://arxiv.org/abs/2001.00050
2: https://arxiv.org/abs/2001.00050
In the vast majority of cases, planets are assumed to be the same age as their host stars, meaning that if the star is old, the planets are old, and vice versa. For a planet to have survived to old age, it is unlikely that it has a naturally unstable orbit, or it would have been removed or destroyed long in the past. Conversely, for an interaction to occur and destabilize a planet's orbit, the interacting body has to be on the order of the planets mass or larger. In multiple planet systems, all other planets that survive past early age will also be in stable orbits, ruling out interactions with them. Which leaves interactions with bodies from outside the system. While rogue planet sized bodies do exist in interstellar space, the chances of them interacting with another planetary system are incredibly small and can be ignored.
There's nothing here!