CMake, which is kind of the universal standard build system for C++ now, has “fetch content” since v3.11. Put the URL of a repository (which can be remote, but also local, which is handy) and optionally the branch / commit ID that you’d like, and it will pull it into your build directory automatically. So yeah, you can pull anything nefarious that you’d like. I don’t think most people would question pulling and building a library from Github as part of the build, especially if it had a sensible name for the task at hand.

You’ve got that a bit backwards. Integrated memory on a desktop computer is more “partitioned” than shared - there’s a chunk for the CPU and a chunk for the GPU, and it’s usually quite slow memory by the standards of graphics cards. The integrated memory on a console is completely shared, and very fast. The GPU works at its full speed, and the CPU is able to do a couple of things that are impossible to do with good performance on a desktop computer:

• load and manipulate models which are then directly accessible by the GPU. When loading models, there’s no need to read them from disk into the CPU memory and then copy them onto the GPU - they’re just loaded and accessible.
• manipulate the frame buffer using the CPU. Often used for tone mapping and things like that, and a nightmare for emulator writers. Something like RPCS3 emulating Dark Souls has to turn this off; a real PS3 can just read and adjust the output using the CPU with no frame hit, but a desktop would need to copy the frame from the GPU to main memory, adjust it, and copy it back, which would kill performance.

You say that, but elephants, which are the largest animal alive on land today, are surprisingly quiet. They’ve got very padded feet to support their enormous weight, which means they move very quietly.

Now, not seeing them? They were big bastards. Need some trees to hide in.