The Reptilian Conspiracy Theory (a source of inspiration for the Wachowskis sisters) is an abstract concept (sometimes pure entertainment ,sci-fi, internet joke or urban leyend) promoted by several authors based on texts by gnostics, human-farm-archontic theory, chamans, mediums and ordinary internet users.

Story line in a lousy nutshell:
Humans are not at the end of the food chain because the whole world is a big human farm. An advanced alien species masters of time, space, genetics and mental manipulation have created us through directed evolution from apes. This species is using an holographic or virtual AI computer reality on us whose purpose is to produce some sort of “vital energy” (prana, chi, reiki...) through human suffering.

These species have limited our perception and have much higher levels of intelligence and technology but they cannot produce that “energy” by themselves. They can induce thoughts and feelings on us and promote certain systems of believes such us nationalism, religion, politics, history through mass-media or secret human societies and other means to produce more confrontation, suffering and ultimately more “energy”. They can even travel in time to a certain extent and they can make snapshots of the virtual world at any time as they see fit. Even though they have a better understanding of us than ourselves this fake reality is not perfect. When we die a tunnel of light appears which is in fact soul trap. A feeling of utter peace and love will be induced and according to your believes a precisely chosen figure (angel, deceased relative, spiritual master, etc) will appear to persuade you to reincarnate again into this existential video-game or in another different for your own good or "spiritual development". In some existences you play the victim in others you are the predator in others you are a spiritual master allowed to rig the system to certain extend to manipulate people by giving them "false hope". All kinds of ideas from your past such us revenge, guilt, regret or even karma will be used to make you reincarnate again. They can even get twice the energy from you if they decide to make you feel the pain you allegedly caused on others by your fake "free-will". Also they can even make you believe that you agreed your own miserable existence on earth for spiritual reasons or soul-contract and show you how you agreed to remove your own knowledge by a fake AI created past plus an artificially altered perception or “gut feeling” to induce you to think that what you are seeing it's true. (the paradox of voluntary ignorance can be a bitch...)

Liberation/Salvation is attained when you seek empathy towards all sentient beings and accept this world as an illusory manipulating video game, when you seek happiness and high vibration, and you acknowledge that you don't have real free-will because only your soul (or true self) has it and all your perception, feelings, memories, thoughts, psychology etc. can be manipulated therefore you are not ultimately responsible nor guilty of anything. When you die you must not go into the tunnel of light and reject all requests of reincarnation no matter how great the existence promised by the AI machine or lizard in charge can be.

According to this theory when a Buddhist dies a figure of Buddha or another ascended master will appear and will try to persuade the practitioner to reincarnate again because of karmic reasons or just being not good enough in dharma or meditation, then the Buddhist person agrees to remove his knowledge and reincarnates on earth again hoping to attain enlightenment this time...

This conspiracy theory has a lot in common with many religious dogmas including Buddhism. Both tackle the origin of suffering and blame ignorance for it, both talk about a method/process of awakening and self-discovery and both talk about the illusory nature of existence (Maya/Matrix). People who advocate for Buddhism advise you to meditate, people for the RCT encourages you to do anything you need to get a high vibration (I guess that includes not harm yourself or others) eg. "Yoga, meditative sounds, gongs, isolation tanks, lucid dreaming, astral protection, psychology, philosophy, ancient aliens, hypnosis, past-life regression even moderate drugs!" to remind yourself that your all perception can be rigged and in fact is!

Why Buddhism should be any more credible as dogma or even better to attain enlightenment? Both give you meaning, purpose, hope, the promise of a better existence and a path to be followed and both are based on believes such us (Karma, Samsara, Bardos, Simulation hypothesis) that cannot be proven nor disproved whose nature is based not in evidence but speculation and subjective biased personal experiences which are impossible to double-check. Even the RCT is kinder because you don't have to be enlightened nor spend a great deal of time doing hard meditation practices for a remotely possible “shot at liberation”. You only have to know the truth and accept it even when the truth is bad (red pill). Notice how the RCT acknowledges karma as part of the lie because it's unfair to pay for something you don't remember doing because you hardly have free-will and that knowledge is the most precious thing in existence. Buddhism has centuries of experience but the RCT uses the latest technologies such us the neuroscience of free-will, near death experiences, testimonies from alien abductees etc.

Kalama Sutta tells you to question everything with moderation and not to overload the mind but makes clear that you should have a mind of your own and not just blindly follow any leader or dogma. Attachment is a known source of suffering nevertheless most Buddhists even monks seem to be attached to the Buddhist dogma itself, some shave their heads to get more identification other wear mallahs and their reasoning is clearly motivated to protect the philosophy/religion and the Sangha (because they are attached to it), and they rarely do something to break tradition. Doing critical thinking gives you truth and sometimes things are not the way you wish them to be. Plenty of Buddhists fall into this process of happiness/attachment/purpose ultimately doubt and then fear/sadness/disillusionment which is clearly explained in Buddhist sutra itself and by psychology in cognitive dissonance. After all, we are all human and our mind is weak and imperfect and some people need their time to heal so a little understanding and compassion for Sangha is needed here. If so why Buddhism is better than a rehab theraphy center, joining the army, Scientology or some weird sci-fi lizard story? That would depend on the person and their preferences, affinity, tastes and whatever floats their boat instead of a solid philosophical foundation.

Isn't Kalama Sutta just telling you that it's better to be a free-thinker than a Buddhist, at least in some cases?

There is no spoon — The Matrix

What you think you become — Buddhist proverb.