The "ideal world" -- yeah, I've heard of that.
Your point is good, though, and I agree with it. Most of the time, at least. I can imagine edge cases where starring a quote would not warrant starring the original, but in most cases, you're probably right.
As you would've guessed, this is non-trivial to implement. If the quote-starrer has already starred the original, should this result in "no change"? Or should it mean a star just for the quote? Or should this justify a "double star" for the original?
Never mind the cross-site case (as in your example), where the "who starred what" question gets even more complicated.
But yes, this is worth considering.