What is the maximum number of DL PDSCH layers for MU-MIMO spatial multiplexing that you have encountered in a cell with highest traffic?
In theory it should be up to 16 layers for 32T32R AAUs and 64T64R AAUs (vendor dependant this value of 16).
But I doubt it is ever possible to achieve this level of 16 layers with only 32 elements of AAU because it means each layer would need to be generated by 2 AAU elements that means little gain so users would all have to be very close to AAU.
This max DL PDSCH layers parameter is vendor dependant (max value to be set is 16) and can have a value like 2,4,6,8,12,14 or 16.
It helps a lot to increase capacity of the cell in 5G and so users throughput in MU-MIMO scenario.
Then again: what is the maximum value you have seen on the cell with highest traffic as per counters of DL PDSCH layers?