Well that's the thing, those recruiters will keep emailing you desperately until the morning of the layoffs are announced. Facebook's hiring freeze was so sudden that it even caught their own recruiters off guard.
Also what we are seeing is the early stage of hiring cooling. Some companies will start with "soft" hiring freezes, which means no new headcounts but the ones that's already opened will still be kept open, along with back hire for attritions. In those cases recruiters would still be reaching out.
Then there is the "hard" hiring freeze, which means open head counts are taking away, sometimes even impacting people already in the interview process. That's what FB did for all their recent openings under a certain level (<M2 and <E6).
So yeah, recruiting emails alone don't really tell the whole story.