Here’s my understanding as a layman, please correct me if I’m wrong.
SCOTUS could block the creation of a law if it was deemed unconstitutional, but even with a conservative SCOTUS, it’s unlikely they would in this case. As in many cases, SCOTUS didn’t overturn a law here, but rather changed their decision on the interpretation of the law, specifically the Administrative Procedure Act. If congress passes a law that explicitly delegates certain powers to agencies, or codifies regulations that had previously been defined by an agency, that would be harder to fight since the APA, as far as I can tell, does not prohibit it. Warren’s bill is basically saying “if we can’t implicitly delegate power to agencies to create regulations, we should at least be forced to quickly review suggested regulations to prevent them from getting stuck in congress.”
Again, this is just my understanding as a layman. IANAL