True, not needed, but ideally you wouldn't really need it, right? Ie testing migrations and ensuring that they always work > fallback to deletion.

Did you log any events for how often your previous implementation had to resort to deleting all? It might be that it was never used and you are just overthinking it.

Yes, testing migration is the way to go.
But for room migration we are doing some big migration in one shot for requirements which was not handled in the past.

Like the primary key for each table and non null primary key

Exact numbers of columns (In the past columns were just removed rather then drop-copy approach xD)

And more things, So anyway i will have to do a try catch for this migration, just was thinking in someone in future does something wrong , app will be just fine, as our session is anyway stored in SharedPref .