isn't it a weird irony to rely on the big generalization that "[h]itherto the people attracted to philosophy have been mostly those who loved the big generalizations, which were all wrong?"

Yes, you caught the irony. Of course, not all ironic statements are false. There are in fact true generalizations about overgeneralization.

There are indeed questions to which philosophers have given insightful answers. But I feel embarrassed on behalf of philosophers to see such pseudo-questions paraded as their proudest accomplishments. Being is univocal because quantification is univocal; we don't mean different things by 'are' or 'two' or 'all' in different contexts. The best metaphor for truth will depend on our goals. 'The Good' and 'Being' are ambiguous terms, so the question as to their intended sense will need to be clarified before it can be fruitfully pursued. See Peter van Inwagen's Being, Existence, and Ontological Commitment.

(Since I'm citing a philosopher, you know I agree with you to some extent. I just don't like treating Philosophy as a tribe to be defended. Especially not Bad Philosophy. If philosophy is anything worth preserving, it's just a toolbox.)