They would have the same "very serious questions" to answer if they simply abolished the Voice legislation in the event that it was only legislated and not enshrined in the consitution. That they wilfully ignored The Voice. Ergo, there is no difference between legislating it and constitutionalising it. Any Government who ignores one or ablishes the other will have the same set of questions to answer from the same people.
And still in either scenario, nothing gets done to improve the lot of Indigenous Australia.