As far as I know YouTube videos are normalized in volume so that 79% is max volume. And for whatever reason YouTube sets the videos volume from time to time, just in case anyone changed it. So Firefox and pipewire are doing what they are supposed to do, while YouTube's questionable inner workings messes everything up.

Microsoft initiated a fear, uncertainty, and doubt (FUD) campaign against OpenGL around the release of Windows Vista. In 2003, Microsoft left the OpenGL Architecture Review Board -- showing that they no longer had any interest in the future of OpenGL. Then in 2005, they gave presentations at SIGGRAPH (special interest group for graphics) and WinHEC (Windows Hardware Engineering Conference) giving the impression that Windows Vista would remove support for OpenGL except to maintain back-compatibility with XP applications. This version of OpenGL would be layered on top of DirectX as shown here, (from the HEC presentation) causing a dramatic performance hit. This campaign led to panic in the OpenGL community, leading many professional graphics programmers to switch to DirectX. When Vista was released, it backpedaled on its OpenGL claims, allowing vendors to create fast installable client drivers (ICDs) that restore native OpenGL support. The OpenGL board sent out newsletters proving that OpenGL is still a first-class citizen, and that OpenGL performance on Vista was still at least as fast as Direct3D. Unfortunately for OpenGL, the damage had already been done -- public confidence in OpenGL was badly shaken.

The launch strategies for Windows Vista and Windows 7 were both accompanied with an immense marketing push by Microsoft for DirectX, in which they showed 'before' and 'after' screenshots of the different DirectX versions. Many gamers now think that switching from DirectX 9 to DirectX 10 magically transforms graphics from stupidly dark to normal (as in the comparison above), or from Halo 1 to Crysis. Game journalists proved that there was no difference between Crysis DX9 and DX10, and that its "DX10" features worked fine with DX9 by tweaking a config file. However, despite its obvious inaccuracy, the marketing has convinced many gamers that DirectX updates are the only way to access the latest graphics features. While many games participate in Microsoft's marketing charade, more savvy graphics programmers like John Carmack refuse to be swept up in it. He put it this way, "Personally, I wouldn’t jump at something like DX10 right now. I would let things settle out a little bit and wait until there’s a really strong need for it."