I know there are some ATC guys who troll around on here who can perhaps provide some insights, and mods if this may be better suited in a different section please move it

Why is it that an airport like JFK only has one ground frequency whereas airports like ATL, MSP, and DTW (which has 4 charted ground frequencies) have multiple ground controllers? What qualifies airports for multiple frequencies? Is it based on an airport layout or traffic volume or some other factor? It seems like JFK, especially in the afternoon hours, could benefit from breaking up the workload of the ground controller, when in DTW it seems regardless of time of day you have to through 3 ground controllers to get from the gate to the runway.

Just something I was wondering when it took me 45 minutes to get from the runway to the gate in JFK the other day because of frequency congestion and everybody stepping on everybody