It makes the questions incoherent.

This isnt a benefit, it's a sign that the semantics you're giving language fail to actually model its meaning.

The position isnt self-consistent, unless you engage in the typical idealist peformance of pretending not to know what these questions mean.

In the end, idealism is defeated by the very implausibility of this performance. The idealist, is implicated in the rich ontology of the real world by the very use of language itself. Presupposed is this ontology, and the ordinary truth of ordinary propositions requires it.

If the question, "what was here before I existed?" is meaningful, then idealism is wrong. And it is meaningful, therefore it is wrong.