Thanks, Bill, for that lengthy description of your experience with Geni. If I am not mistaken, FamilySearch also takes the position that once you post a tree, they own it.
The problem you describe is especially poignant because it is so personal, but it is part of the broader problem that the online genealogical websites are vast digital garbage heaps of misinformation, with here and there just enough true data to keep drawing us back to them. I have lost count of the number of rabbit holes I descended into in pursuit of the sources for entries regarding my ancestors. I almost always come away with nothing substantiated but a mounting resentment toward careless amateur genealogists who post nonsense. My own opinion is that it is best to restrict your usage to digitized records and completely ignore online trees. You may miss out on something helpful, and fear of missing out is a powerful psychological motivator, but you will enjoy many hours of life otherwise wasted.