In addition to just the total amount of spectrum, coordinated scheduling between towers in the cellular standards helps with cooperative management of interfere

In addition to just the total amount of spectrum, coordinated scheduling between towers in the cellular standards helps with cooperative management of interference. Some of this is just now happening in 802.11ax, but without the high-speed non-microwave connections that celltowers in dense areas enjoy to coordinate over. 5G-NR also allows coordinated multipoint transmission, which you can think of kind of like MIMO but from multiple towers instead of just multiple antennas on the same tower. I don't know if this would ever be feasible in consumer WiFi equipment due to the challenges of synchronizing clocks across the different APs.