They legally own the assets. Taking them off Steam if the title is no longer abandoned by the publisher is a 100% reasonable decision, so you need to understand this is above and beyond what the publisher needs to do.
An outcome like this more than likely means the folks working on the rerelease are fans of OpenTTD and worked internally to protect it.
An outcome like this more than likely means the folks working on the rerelease are fans of OpenTTD and worked internally to protect it.