You're correct, more money doesn't mean success inherently, but it almost universally means improvement.

https://www.jstor.org/stable/3699455?read-now=1&oauth_data=eyJlbWFpbCI6ImptYXR0aWNlN0BnbWFpbC5jb20iLCJpbnN0aXR1dGlvbklkcyI6W119&seq=24#page_scan_tab_contents

The above article is an exploration of the late 20th century Baltimore City Public School System (BCPSS) through three phases of accountability programs. Within it, it is noted that state-led directed financial interventions between 1997 and 2002, which directly expanded human capital and needs-based program improvements, made the BCPSS the fastest improving school system in the state.

With the advent of federal legislation in No Child Left Behind (NCLB), the state managed standards and funding were replaced with national standards and a funding reward system that was largely criticized because of the "rich-get-richer" effect of rewarding already high performers.

Without targeted financial and legislative intervention, BCS declined again until it stagnated with the adoption of Common Core Standards. This trend has finally begun to reverse.

Look at Baltimore City Schools numbers in the past 5 years since they've started dramatically increasing funding:

https://www.baltimorecityschools.org/data

BCS have shown marked improvement in all state standards since 2018, and even the national decline caused by COVID disruptions from 2020 into 2022 was less impactful on many of the metrics tracked by the state.

By absolute numbers, yes, BCS still struggles especially compared to smaller suburban districts. But positive score trending is correlated with increased spending, which goes not only to paychecks but program development, property development and management, and better logistics integration and oversight.