of the present day, Canaan was incredibly wicked. As evil as the world is right now, there are still some sexual sins (like incest and bestiality) that are frowned upon. No doubt there are people committing them, but they're still considered crimes. Unlike homosexuality, which is "socially acceptable", most people still find incest and bestiality abhorrent (and rightly so). But Canaan embraced them. Leviticus 18 gives us a long list of forbidden sexual practices (also outlawing child sacrifice), and just before that, God singles out Canaan for special mention:
Do you think perhaps you had the answer there. If Ham defiled his father and his mother by having sexual relations with his mother and Canaan was the offspring. That still makes Canaan to be one of Ham's children.
Noah's wife's is also Noah's nakedness.
Leviticus 18 Authorized (King James) Version
6 None of you shall approach to any that is near of kin to him, to uncover their nakedness: I am the Lord. 7 The nakedness of thy father, or the nakedness of thy mother, shalt thou not uncover: she is thy mother; thou shalt not uncover her nakedness. 8 The nakedness of thy father’s wife shalt thou not uncover: it is thy father’s nakedness.
That's definitely possible. After all, Moab and Ammon were neighbours of Canaan and similarly depraved. Their foundation was the incest between Lot and his daughters. So Canaan could well have had similar beginnings.
Reuben was judged because of what he did with Bilhah, something that impacted all his descendants:
Reuben, thou art my firstborn, my might, and the beginning of my strength, the excellency of dignity, and the excellency of power: Unstable as water, thou shalt not excel; because thou wentest up to thy father's bed; then defiledst thou it: he went up to my couch. (Genesis 49:3-4)
Now the sons of Reuben the firstborn of Israel, (for he was the firstborn; but, forasmuch as he defiled his father's bed, his birthright was given unto the sons of Joseph the son of Israel: and the genealogy is not to be reckoned after the birthright. (1 Chronicles 5:1)
If Ham committed the sin that Reuben did (even worse though, because it would have been with his biological mother), then it would certainly make sense that Canaan was cursed because of that. In any case, this is certainly a sin that God judges quite severely.
I think you're going down the wrong track here. Let's read that passage in Genesis again:
Gen 9:20 And Noah began to be an husbandman, and he planted a vineyard: 21 And he drank of the wine, and was drunken; and he was uncovered within his tent. 22 And Ham, the father of Canaan, saw the nakedness of his father, and told his two brethren without.This is specifically talking about Noah being drunk and naked in his tent, not his wife. Also, when Reuben defiled his father's wife/concubine, (and other places where sons took their fathers' wives) it is specifically spelled out in the Bible, not left to speculation.
That being said, I've always wondered what Ham did that was so wrong. I mean, did he know his father was naked before going into his tent? Did he know that he would end up seeing his father naked and do it on purpose? Should he have knocked first before going in in the first place? I also have to wonder about Ham's attitude when he told his brothers about it; if he was kind of snickering and joking about it, then yeah, that would have been extremely disrespectful and worthy of reprimand.