Earlier quoted context omitted.
That just reflects it's status as the de-facto starting point. You could equally state that it's too bad that very few build anything memorable with HTML.
Well yes, a starting point - but not also the ending point at the same time. And by memorable I meant based on bootstrap but with own "personality", not bootstrap's.
Though I don't use their site I think https://kippt.com/ did a pretty good job at making bootstrap their own (though you can't really tell the good ones are done in bootstrap)