[illiarian]

Because more often than not is has to be implemented on OS level, and no one wants to do that for many many reasons, and patents are probably the least of it.

For example, for most modern formats software-only encoding is very slow, and you really want to have hardware support for it [1]. But to add hardware support to increasingly complex and varied specs is not a decision you make lightly.

[1] Google is forcing companies to support its codecs in hardware on pain of removing Youtube e.g. https://arstechnica.com/gadgets/2021/04/roku-vs-google-part-...