> The browser engine should become as the Linux Kernel: one engine and different distros.
Try spending a month with a BSD - personally, I recommend OpenBSD, or (yes) macOS. Alternatively, try ZFS where you've previously used mdadm+lvm+luks+etc.
The difference is like sitting in a chair that has all of its screws tightened. You only notice how bad was your previous chair once you feel there's no wobbling.
That's more of a distro thing than "Linux being a few screws loose".
I vastly prefer the OpenBSD kernel too, but if you use a distro that does things properly such as NixOS, the BSDs are the ones that feel wonky.