Welcome to the Wikipedia version of genealogy - and it has the same problems, for the same reasons (do you cringe when you hear technobabble like "crowdsourcing," which implies that if enough people recite the same thing, it must be true?)
Unfortunately, your observations are the same thoughts many of us have had, but there is no practical way that the type of quality control you would like to see could actually be put in place. Among other things, the blatantly wrong trees start to take on a life of their own, if enough of the clickologists stumbled on them. There are a few minor reality checks in place in the system (for instance, if entering a person "from scratch," you will be alerted if the mother's date of birth would make her three years old - or already dead - when the "child" was born). But amazingly, there is no such reality check when people click and merge composite profiles they have found - so the bizarre errors get perpetuated over and over. And if your tree is the outlier (but it's correct), you certainly don't want some Ancestry person to be able to override the correct information in your tree in favor of what "the majority" has in their trees (even though they all just copied from each other).
Really, there is nothing you can do except just do you own thing (sorry, I grew up in the '70s). Some people have gone private out of frustration over these issues, and some keep slogging on and hoping that the actual facts will overtake the weird fiction - no way to know, at this point! But if it helps at all, you certainly aren't alone.