We use several remote job board within my company to hire candidates. AFAICT we didn't hired anyone from these jobboard. But it definitely creates lots of candidates to review.
OP here - Yep, job boards nearly always create more volume. After running one for several years, we see great job descriptions attract great candidates and vague job description attract, well, average candidates :)
Tons of small/large companies are turning to job boards, especially when it comes to hire remotely where you never know where your next employees lives.