VTK-m Windows should support CMake 3.3 with Ninja.
VTK-m checks for requiring 3.11 should be when using the MSVC generator not the MSVC compiler.
https://open.cdash.org/viewConfigure.php?buildid=5383157
So the logic of
if(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
cmake_minimum_required(VERSION 3.11 FATAL_ERROR)
endif()
should instead check ${CMAKE_GENERATOR}