Trying to put the potential negative consequences if this pause stays in place aside, it's going to be fascinating to see the immediate ramifications of this even if it's just bluster. I'd imagine there's going to be plenty of people/groups expecting committed funds to show in a bank account at the first of the month, and any confusion/issues/delay is going to have a wildly long tail of knock on effects.
The long tail of knock-on effects is more severe than you could even imagine -- this is going to immediately ruin the NSF grant review process, which is already lengthy and fragile and backlogged.