Low FPGA Resource Utilization Observed in AN552_Corstone_SSE300_with_Cortex_M55_and_Ethos_U55_for_MPS3_4_0

Hi 

i am following the document AN552_Corstone_SSE300_with_Cortex_M55_and_Ethos_U55_for_MPS3_4_0 (Partial Reconfiguration Design), we can find here  https://developer.arm.com/documentation/dai0552/c?lang=en . After generating the bitstream, the resource utilization appears to be quite low, as shown in the snapshot of mps3_fpga_top_utilization_placed.

LUT utilization is 6.85 %

BRAM utilization is 13.03 %

But LUT and BRAM utilization mentioned in Arm Corstone SSE-300 with Cortex-M55 and Ethos-U55: Example Subsystem for MPS3 is 45 % and 50 % respectively.

Can anyone help me why these utilization difference are coming?