You state that smoking weed has carcinogenic effects similar to tobacco which very obviously is not the case. They are completely different drugs with completely different side effects. Smoke from marijuana does not equal smoke from tobacco. I am not saying its without negative consequences but they are apples and oranges.
Of course we have research on smoked flower. 1000s of years of research. Mankind has been smoking this plant longer than recorded history and Ill take that any day over the literature at pubmed. I would love for the feds to allow more research of course but its still schedule 1 so not much to be done.