Earlier quoted context omitted.
This is a pretty bad argument, as exactly the same can be said for the Servo/Firefox codebase
See above: it's true, but at least FOSS born and evolved projects may be known by "early" devs that see project evolution during it's time, on contrary when a company release million SLOC no one really know anything... Anyway, in general my line is that all "modern browsers" must die, because browsers should be browsers, not "platforms" and websites should be hypertext, not application... I really dream a modern Plan…
Do you know the history of Blink? It was forked from Webkit, which was forked from KDE's KHTML and remained open source all the way. So you argument also explains to Blink.