(Note: For a somewhat complex software project, trying to build with a build system that is not "officially" supported by the upstream developers will be a huge task, if possible at all. So, you better stick with what the developers recommended!)
VS has command-line tools available as well as the ability to use CMake files. So using the VS compiler to build this project outside the IDE is theoretically possible, though it probably would require some hand-holding to get the compile process to work.
Have you considered running Linux? If you can get your hands on a 2nd computer, try it.
A distribution like Mint or Kununtu will not be completely unfamiliar to a Windows user. If you can move from Windows to a Mac, you'll find using Linux trivial.
I don’t think telling OP to change his OS is very helpful when OP wants to compile on Windows. It’s one thing to cross-compile from an extant system (not easy), but it is a whole new level of grief to set up yet another OS just to target your current OS...
That said, the documentation right at the start says very clearly it is a Linux Desktop application, and in order to compile on Windows you will need MSYS2.
MSYS2 is indeed very easy to set up. The trick is properly installing and configuring the required libraries, such as GTK+, which is not so easy, even with the pacman tool (MSYS2 is an Arch linux distro).
The documentation has all the required steps. Like I said, the most difficult part is making sure you install all the dependencies. Often you can get the required command for your distribution by googling something like “ubuntu install gtk+ dev” or “msys2 install gtk+ dev”.
For the latter, Google listed a link for the GTK documentation:
https://www.gtk.org › docs › installations › windows Setting up GTK for Windows
Reading down it provides the pacman commands not only to install GTK, but also how to do other useful stuff, like make sure your compiler is installed and how to compile and bundle your GTK application.