I set up identical profiles and passed all the relevant quizzes at Triplebyte, Hired, and LinkedIn (all 3 offer timed, multiple choice question tests with limited retries), but only LinkedIn was able to match me with opportunities willing to pay what I was asking. Triplebyte and Hired both let you set a floor salary, but have no ability to set a floor total compensation, which meant it was effectively worthless for determining if a company was competitive for me.
In Oct-Dec '22, I got ~400 LinkedIn recruiter messages (3% with high enough total comp), ~20 triplebyte messages (0 with competitive comp) and ~10 hired messages (0 competitive). None of these recruiters were connections beforehand on any platform, so it's just representative of the total number of recruiters on each platform. (In case anyone is interested, I also cold-applied ~20 places, and none of those resulted in me making it past the hiring manager stage, if that. I ended up with 2 offers, both from random LinkedIn recruiter outreach.)