That is unfortunate.
Much like the last time this came up, this decision was brought about due to testing and player feedback. As such the only way I'd consider reversing the decision is if there was an overwhelming amount of critique wishing for the ability to rename Dave to be brought back as a mechanic.
Even then, if your desire to play this VN hinges solely on renaming Dave, I'm happy to look into other VNs that might be more suitable to your needs if having the MC 'nameable' is an important feature.