In paraconsistent logics one cannot use a proof of "X" and "not X" to prove any arbitrary statement, so it can indeed still be useful. However we still need to

In paraconsistent logics one cannot use a proof of "X" and "not X" to prove any arbitrary statement, so it can indeed still be useful. However we still need to formally reason about the system to be able to establish that it is indeed a paraconsistent logic (that the principle of explosion doesn't apply).