People just didn't call them GPUs before 3D acceleration, just referred to them as graphics cards. The first thing people noticed were that blocky pixels were replaced with a smooth bi-linear, tri-linear or anisotropic interpolation (depending on game settings).
I had many different graphics cards. When Deus Ex invisible war was released, I bought a PNY Verto graphics card that was among the first with DirectX 9 compatibility and programmable shaders, these early cards capable of stencil shadows did not have an external exhaust for hot air, so I had to open my window during winter and sit with warm clothes to avoid overheating the CPU with hot air from the GPU. Then it turned out that the game wasn't even a good sequel to the original.
Microsoft replaced DirectSound with a cheap software reference implementation, so that games would sound the same on PC and XBox. In theory, it would be nice if they could have the same features as Sound Blaster Live (sounded like having an orchestra in your room with surround speakers), but Microsoft were no sound specialists (sounded flat and stiff without any environmental feeling nor smoothness). If you don't have hardware sound acceleration anymore, it's much better to just call the media layer directly and write your own sound mixer writing a stream of waves directly to the speakers for more control over the same performance.
Direct3D 11 was the best API when it comes to balancing power and usability, but Vulkan lets me play the latest AAA games on Linux.
Direct3D 11 has annoying manual padding of shader arguments, which is padded for different machine word lengths between CPU and GPU. Direct3D 12 does not new features I want so far, but staying with Direct3D 11 and Windows 7 forever is obviously not a long term solution.
When my new computer came with Windows 10, the system broke backward compatibility with so many USB gadgets that I could not even connect to the internet. Windows 7 was no longer supported by new motherboards. Then I installed Manjaro Linux and all my gadgets (router, MIDI synth, stylus, web camera) worked either out of the box or with one line to install them. Installing GPU drivers was actually easier on Manjaro than on Windows.
Vulkan still has the legacy from OpenGL of associating samplers with images, which can be worked around but coupling unrelated things makes it harder to keep an engine's implementation clean. None of the GPU APIs offer the same functional purity that a software renderer can offer, because they all tie resources to contexts, making regression testing more difficult.