"Why is it that package managers are unnecessarily hard?" — or are they?

At the moment the top rated post in In the C++ subreddit is Why is it that package managers are unnecessarily hard?. The poster wants to create an application that uses fmt and SDL2. After writing a lengthy and complicated (for the task) build file, installing a package manager, integrating the two and then trying to build their code the end result fails leaving only incomprehensible error messages in its wake.

The poster is understandably frustrated about all this and asks a reasonable question about the state of package management. The obvious follow-up question, then, would be whether they need to be hard. Let's try to answer that by implementing the thing they were trying to do from absolute scratch using Meson. For extra challenge we'll do it on Windows to be entirely sure we are not using any external dependency providers.

Prerequisites

• A fresh Windows install with Visual Studio
• No vcpkg, Conan or any other third party package manager installed (more strictly, they can be installed, just ensure that they are not used)
• Meson installed so that you can run it just by typing meson from a VS dev tools command prompt (if you set it up so that you run python meson.py or meson.py, adjust the commands below accordingly)
• Ninja installed in the same way (you can also use the VS solution generator if you prefer in which case this is not needed)

The steps required

Create a subdirectory to hold source files.

Create a meson.build file in said dir with the following contents.

project('deptest', 'cpp',
    default_options: ['default_library=static',
                      'cpp_std=c++latest'])
fmt_dep = dependency('fmt')
sdl2_dep = dependency('sdl2')
executable('deptest', 'deptest.cpp',
   dependencies: [sdl2_dep, fmt_dep])

Create a deptest.cpp file in the same dir with the following contents:

#include<fmt/core.h>
#include<SDL.h>

int main(int, char**) {
    if (SDL_Init(SDL_INIT_VIDEO|SDL_INIT_AUDIO) != 0) {
        fmt::print("Unable to initialize SDL: {}", SDL_GetError());
        return 1;
    }
    SDL_version sdlver;
    SDL_GetVersion(&sdlver);
    fmt::print("Currently using SDL version {}.{}.{}.",
               sdlver.major, sdlver.minor, sdlver.patch);
    return 0;
}

Start a Visual Studio x64 dev tools command prompt, cd into the source directory and run the following commands.

mkdir subprojects
meson wrap install fmt
meson wrap install sdl2
meson build
ninja -C build

build\deptest

This is all you need to do to get the following output:

Currently using SDL version 2.24.0.

Most people would probably agree that this is not "unnecessarily hard". Some might even call it easy.