Comment by grishka

Because high-speed internet became omnipresent. The act of making a software release stopped having a cost associated with it, like having to print CDs and ship them to stores. Software transitioned from meaningful releases, each of which needed to be as bug-free as possible and had to be sold to users as a genuine meaningful upgrade, to this pathetic eternal beta we now have.

Also because everyone seems too scared to practice adversarial interoperability.

Also because SoCs are now a thing which allows unhackable secure boot and other DRM-like functionality that prevents people from modifying their own devices to act in their own interest, or, as is the case with Android devices, allows it but punishes the user for having gained full access to their own device.