I am using MSYS2 as recommended on the website
Assuming that you are following strata’s instructions, the cmake installation you are using comes from a MSYS2 package. That is not maintained by upstream CMake developers and has some extra patches.
create … Platform/MINGW64_NT-10.0-18363 to use this system
The MSYS2 version of CMake on your system is somehow misidentifying the system name. It shouldn’t have the platform version number in it.
I suggest asking for help from strata first, since their instructions indicate they have experience building on MSYS2. Or, ask over on an appropriate forum for MSYS2 since they maintain the cmake package in question.