default or selected kernelversion does not have config value CONFIG_ARCH_TASK_STRUCT_ON_STACK.
Result is shown for kernelversion 6.9.9

CONFIG_ARCH_TASK_STRUCT_ON_STACK (not configurable)

configname: CONFIG_ARCH_TASK_STRUCT_ON_STACK

Linux Kernel Configuration
└─>General architecture-dependent options
└─>ARCH_TASK_STRUCT_ON_STACK
In linux kernel since version 4.2 (release Date: 2015-08-30)