I hope you are doing well.
One can try removing unused reserved memory nodes in the device tree if present.
One can add the below option in the kernel configuration.
CONFIG_CC_OPTIMIZE_FOR_SIZE=y
Please try to get more information about various processes using the below command.
# top
# ps aux
However, with Wayland build it seems to be normal memory usage.
Thanks & Regards,
Sanket Parekh