As a lucid dreamer in my adolescence[1], my interpretation of Inception is perhaps more literal than most. The trick to regular lucid dreaming is to prepare yourself beforehand--to prime your mind (conscious, subconscious, w'ever) to distinguish dreams from reality. Then when you're in the dream you're more likely to come to the realization that you're dreaming. Not unlike the task in Inception, except you're seeding your waking mind with an idea that comes to fruition while asleep. And just like in Inception (and perhaps a little like the Matrix), the second step once you realize that the reality is false is to stay calm and in control. And I mean this literally. If you accidentally exercise muscle control of your real-life body you'll snap out of the dream--the mechanisms for controlling consciousness, muscle control, and wakefulness snap back.
In other words, to me Inception proves the exact opposite--that you can distinguish false realities as long as you're aware that false realities exist. And the movie is filled with moments where targets either realize they're in a dream or come close to figuring it out--a key source of suspense. Indeed, the son had training on how to come to this realization. The strategy in the movie was to leverage his relationship to his father as a distraction--his emotional need for the validation of his father hindered his enhanced ability to distinguish the false reality.
FWIW, I love both the Matrix and Inception. But to me the Matrix is more fantasy and philosophy while Inception is a movie made by someone fascinated with the real-life practice of lucid dreaming. The only fantasy element in Inception is the linking of minds; everything else hews quite closely to the real experience of lucid dreaming (e.g. mirrors as a mechanism for inducing the subconscious to spontaneously generate a new environment), modulo the dramatization.
[1] Like most people I just happened to figure out a routine for lucid dreaming without even knowing it was a thing. Only later in life did I meet people who had similar experiences, and who likewise were unaware it was a thing other people did. Turns out it's not uncommon, but usually only adolescents as lucid dreaming is easier while the brain is developing and the mechanisms for regulating muscle control and consciousness falter more easily. In a sense lucid dreaming is very similar to a sleep disorder. The prevalence of sleep disorders such as sleep walking and sleep paralysis is much higher among children than adults. Lucid dreaming as an adult takes much more practice and determination than I can muster. Occasionally I have experiences close to lucid dreaming (awareness that I'm dreaming while in the dream), but having had real lucid dreams I know it's not the same thing, even if they're more lucid than typical. In a real lucid dream you're 100% conscious and in control of yourself and your movements--not necessarily the environment. For example, many people have dreams where they try to fly but can't quite do it. Maybe they can jump really high, but no matter how hard they try there's something hold them back. In a lucid dream I can fly like superman on a whim, and otherwise explore the space as if I'm in a video game. At one point I had a nightmare--a recurring nightmare, but this was the first time since I had begun lucid dreaming. When I woke in the morning I followed my routine and reentered the nightmare and was able to fight the monster. But it wasn't particularly cathartic and exciting because I knew it was just a dream. I actually spent most of the dream walking around the nightmare and checking things out, including the monster. It was the last time I ever had that nightmare, though.