Right, but they pay a different cost there that isn't listed:
"It's not entirely compatible with the existing language"
private and multiple inheritance do not work, for example (yes, i know some of this is fixable, but some is not)
public __gc class one { int i; };
public __gc class two: private one { int h; i = h; }; //error
__gc class a {};
__gc class b {};
__gc class c: public a, public b {}; //will produce an error
private and multiple inheritance do not work, for example (yes, i know some of this is fixable, but some is not)
etc