ddc-control is a simple utility to get / set display's VCP parameters via DDC (Data Display Channel). It runs on GNU/Linux and Windows. Big thanks to @arcnmx for providing the necessary rust libraries that made it possible.
Usage:
$ ./ddc-control -m <monitor_number> get-vcp <vcp_feature_number>
$ ./ddc-control -m <monitor_number> set-vcp <vcp_feature_number> <value>Example:
$ ./ddc-control -m 1 set-vcp 0x60 0x0F # Set monitor input to DisplayPort