What makes a job verified in this case? You can easily verify a firm exists, but that’s not really the critical part. The question “is this a ghost job with no intention to be filled” is the real struggle.
On top of this, you also cannot verify if the position was filled through another job board. The company/HR might say "we filled it through a different portal" and in most portals, expired listings don't show up and there is no way to verify if they actually did hire someone from there.
Put some money on the line. I'm not an economist but you could structure a market where you cannot just take up mental space in the job market for practically nil. That's the current malincentive, that companies put up job listings they have no intention of filling, even when candidates who are qualified by their own criteria apply. The current job market maladies are a perverse incentive of the price of posting a job and applying for a job are effectively nil, the spread is too big for anyone to make the trade.
Interesting proposal, but I think it would take a good size of money. Maybe 50% escrow of first year salary?
Yeah something like that. A breakup fee between the job board company and the hiring company: “if you don’t hire someone within 90 days we keep half of the salary.” But there’s not much incentive for the hiring side to do this!