Once again, soft deletion is theoretically a hedge against accidental data loss. As a last argument against it, I’d ask you to consider, realistically, whether undeletion is something thats ever actually done.

Source: Soft Deletion Probably Isn’t Worth It – brandur.org

This is a well-reasoned piece that, unfortunately, probably won’t change the status quo. Soft-deletion just feels safe. It’s psychological, not technical. But yes, I agree, a separate table makes a ton of sense.