I guess that's one way to guarantee development slows down to a crawl, but in no way would it increase trust.
nationalization to me simply means the government is their main customer and stakeholder, and shield them from liability, governance, and openness. not that the frontier labs become part of the government per se.
I personally believe they already have this, why would the current government at least want to formalize this when it can have it with no public discussion.