Maybe! Any kind of dealings with the Sentinelese will have to be pretty cautious if we want them to be able to maintain their autonomy at all, though.
If that’s the idea, we’re already doomed.
Think of it as making a backup of your work. You don’t know with certainty that you will need it. You don’t know with certainty what changes will occur between your backup and later on when or if you decide to revisit it.
But if you do need it, you will be very glad you had it.
Take, for example, the fact that we are gene-modifying wheat. It strikes me that we may not need a civilization-destroying catastrophe to benefit from having some unmodified-relative-to-1950 wheat set away in storage, if only to compare to down the line to see exactly what we changed, or for anthropological reasons.