It seems much more appropriate to write "Islam doesn't teach people to be corrupt. Corruption is a function of poverty, not religion. For example countries of religion X aren't islamic but report similar signs of corruption." Calling people bigots seems less appropriate and counter productive.
Someone who makes even a rude assumption about a people isn't necessarily a bigot. They could just be wrong and you could correct them without insulting them in the same you would hope people would correct you if you said something inaccurate.
I think its very clear that the auto-hatred of Islam is driven by bigotry and fear. Anyone who does even a cursory examination of the subject can see it does not, in fact, promote corruption.
You might be pantywaiste about calling out bigotry online, but I'm not.
Someone who makes even a rude assumption about a people isn't necessarily a bigot. They could just be wrong and you could correct them without insulting them in the same you would hope people would correct you if you said something inaccurate.