Apple and Google do not share code post-fork, and Apple denies Google ~30% of the browser market, so using "mono-" is wrong. Google has a search monopoly, but not quite a browser and definitely not a browser engine monopoly.

The KHTML/WebKit lineage is more a monoculture in its older parts, but I say this is evolution in action (cf. successful alleles and haplogroups across many populations).

So we are not "contributing" much to any monoculture or monopoly, and the alternative is dying on the wrong hill, as I just posted. Any substantive response?