We should always respect others' freedom of speech just like we respect our own lives. At the same time, we should also keep an objective attitude towards the criticism from other. If what they said is true, we change our wrong behaviors. If what they said is not correct, we still need to remind us of avoiding mistakes. Bad words are useless of solving disputes.
Things are very simple. You just mentioned some shortcomings existing during the parade but somebody were not very happy about it. They began to mention how difficult they prepared for it baba.... To be frank, I respect their efforts but this does not mean that the parade is perfect. What you mentioned are truth, which is undoubtable. Your suggections should be taken into account instead of being blamed.