An electric cargo van is both a cargo van and a commercial electric vehicle. The practical choice is therefore whether a gasoline or diesel cargo van should continue serving an assignment, or whether a suitable electric cargo vehicle can take over. Keep the cargo requirement fixed while comparing the complete operating arrangements.
Retaining a conventional van can make sense when a required body or equipment package is unavailable on the electric candidate, usable charging does not fit the work, or the transition would leave an unresolved service gap. Those are specific constraints to assess and revisit, not proof that conventional vans are always preferable for cargo work.