How about proving that my comment was unjustified by outlining what you know of the various anaerobic metabolisms and what chemicals would be toxic to them. Experience with oxygen-based life is not a real qualification.
I like the way you try to assert yourself over others with comments like these. Have you been approaching others this way for 72 years? Really?
Think about it, Keith. It's based off of what we do know about life. Isn't that how science is supposed to work?
For oxygen-based respiration, CO2 is toxic because CO2 has to be removed from hemoglobin before oxygen can by bound.
CO is particularly toxic because it binds more strongly to hemoglobin than does oxygen.
SO2 and SO3 are toxic because of their effect on the lungs, I think.
Real science is based on finding out the important and relevant facts, by literature search first, and then by experimentation if necessary and practical. There is no scientific merit in wild speculation without at least some supporting facts.
What for example, are the facts you know about life which support your position?
Are there any point from your 'toxin' post which you want to discuss further?