That is almost certainly the union's doing. Unions help push back against the downward pressure on wages from employers (who are passing on the downard pressure from investors and the public).
The same thing happens at the vast majority of US universities whose faculty aren’t unionized. In fact, per [0], the two thirds of adjuncts make under $50,000 which is less than half what the union negotiated.
OK, but roughly 100% of the US has lower living costs than Berkeley too. $50,000 (especially with solid benefits) is a middle-class salary in most places.
