"We've come to the point where building the browser from scratch takes more than building the OS itself."
It doesn't. It took ~5h to build a tiny (~150 MB) complete system (Linux kernel + Yocto based "OS") from sources on 4 core PC few years ago. With modern CPU, I guess, it might be 3h or so. On the side note, the build process generated >50GB of files.
I admit I have not done so in a while, but I vaguely remember building Net/OpenBSD from source was faster than that on moederately powerful hardware (Core2 Quad 2.4 GHz, 8GB RAM, no SSD).
I think NetBSD took ~2.5 hours, including building its toolchain.
It doesn't. It took ~5h to build a tiny (~150 MB) complete system (Linux kernel + Yocto based "OS") from sources on 4 core PC few years ago. With modern CPU, I guess, it might be 3h or so. On the side note, the build process generated >50GB of files.