facts are simply statements that can be proven true or false dependant on evidence. without evidence there is no fact. You can't make wild assumptions about things and say something is possible without any shred of evidence.

Use occams razor, the simplest explination is likely true. the simplest and most obvious explaination for dreams is that they occur in your mind. Sure, you could be transported to some 9th dimension by some alien being which magically erases your memory...but this is a far more complicated than random nerve firings controlled by your subconcious (or in the case of lucid dreaming concious) mind. The likelyhood of "shared dreams" would depend on the existence of telepathy. The existance of telepathy can only occur if there is some sort of magical transmitter embedded in your brain. The existence of a transmitter depends on..well..magic. However, the fact that you both WANT to have shared dreams, and so you INVENT them and change the facts aroudn passively to fit the other person's story is far more reasonable and therefore a far more likely conclusion.

To abandon reason is to abandon truth, technology, and humanity. Without reason there is no concrete order to anything, and the world becomes one huge mystical fluffball with no rules or laws. It is true that our evidence is based off of technology, but a good deal of evidence points towards dreamsharing being impossible and dreams just being a mindset. Beleive what you want, but study after study concludes that such nonsense is not naturally possible.