I have been using Adobe Illustrator since version 1995, ver 5 (the real version 5), and have used all of the different major versions since. It seems that the snap to point feature while using smart guides will snap to anything except what I want it to. As an example, while using the pen tool, I used to be able to "touch" a point that I want to snap to, and the tool would remember that. Now, I will be directly on top of a path or point that I want to snap to, but the tool is giving a point somewhere else on the other side of the dartboard preference.
Seems like the developers at some point completely scrapped the older code for this feature and started over. It is no longer a reliable or useful tool, and most of the time, it is just an act of frustration.