You will think it's less beautiful when you ship that game on several platforms and find that it has different bugs on each platform, on each hardware version,

You will think it's less beautiful when you ship that game on several platforms and find that it has different bugs on each platform, on each hardware version, and on each driver version. And most of these bugs you can't fix or work around, you just have to bug the vendor and hope they ship a fix in a few months, which they usually won't because your game is too small for them to care about. This happens in other APIs too (we definitely had it happen with DX11), it's just that OpenGL is a lot more complicated than anything else due to its history, so it has proportionally more bugs.