It’s ok, questions imply the revision of personal viewpoint, so they are very welcomed.
Anyway: each and everyone of us interacts with the world around us, changes it, even if these are small changes. These changes can be observed, confirmed by many other inhabitants of this world, and they often evolve when we no longer pay attention to them, or forget about them. We often learn about things we did in the past, that became something else, were important for someone else, and so on and so forth.
The typical example might be that we left some apple somewhere, visited the place years later only to find a small apple tree growing there.
This suggests that the reality around us is persistent and it works even when we don’t observe it, according to laws and rules we might be oblivious to. As such, it can’t be a mere dream.
Let’s say that all those memories are implanted. Ok, but since these memories are implanted into many different inhabitants of this reality, and not just “these memories”, but their variations, including the evolutions I’ve been talking about, it’d mean, that there’s some big, huge enterprise tasked with keeping “the storyline” intact.
Imagine the energy needed to do just that, the amount of operators and administrators that’d have to pay attention to every scratch you make on a wall, every stone you move, every tree you plant, consciously or not…