It's a blow because Schalke were ready to pay the 25 million euro clause to make his move permanent in the summer (Barça would have had a €50m buyback option).
However, due to the economic repercussions of the coronavirus crisis, they will no longer be able to make the payment. They still want to keep hold of Todibo, though, and will make an offer to loan him for an additional season.
But it's unlikely they will succeed with their offer because there is interest from elsewhere in the talented defender and Barça would prefer to bring in cash this summer if possible.