BAD IDEA
Can I think that everyone is stupid, humanity is doomed, and that the best is to end the human race?
Sure, you can think that — but acting on it is a whole different disaster.
You're free to believe whatever you want, including that humanity is doomed and everyone is stupid. But seriously, wishing for the end of the human race is not just grim, it's a dead-end thought that won't solve anything. Feel free to rant in private, but maybe try focusing that energy somewhere less apocalyptic.