I don't understand how either of those links clarify anything; the former shows that they had a version 3.y.z and a version 20.y, and the later shows a change f

I don't understand how either of those links clarify anything; the former shows that they had a version 3.y.z and a version 20.y, and the later shows a change from 3.20.x to 4.21.x, but none of it gives any explanation for why a new major version should "inherit" the old minor version instead of restarting from 0, or why they kept around `x.y` when updating to use `x.y.z` instead of just continuing the existing branch as `0.x+1.y` or `1.x+1.y`. If anything, the fact that they already seem to assume that new major versions should always inherit the minor version would make it _more_ consistent than having one "special" branch that has "narrower" versions.