People calling it a “hard” problem simply parrot the narrative they see other engineers who have tackled it in leadership positions adopt. The reality is it’s a “Dirty” problem. The equivalent of a sewer cleaner in the old days that is a thankless, low pay, low career prospect, riddled-with-politics , nightmare.
Look up the salary bands for roles in spam fighting. The top 5% probably make bank and even that is not wildly large amounts relative to the valley (~$650k TC which is director level)
The LARGE pools of spending go toward maintaining an army of contractors that get passed down a barrage of things that some teams flag through automation. Same at twitter as it is as Facebook and Google. You need only hit up LinkedIn for the right search keywords to find the contractor hotspots.
The point being, Paul is right. If these platforms wanted to solve the problem, the smartest hires would go there motivated by a culture enabling high impact and good compensation.
The hell hole that is moderation operations would make even those guys with the Six-Sigma-black-belt-world-championship-something ops degrees shed tears for how soul destroying the environment is to work in.
Source: Have friends in these roles. Seen it play out a bit more than a decade at this stage.