Are Romulans, Vulcans and Remans the same race? I know that around the 4th century Vulcans who rejected the teachings of Surak (whom they call The Dissembler) left Vulcan to go to Romulus, but who are the Remans? According to Memory Beta, they are betrayed miners who were turned into slaves after voluntarily going to mine Remus, if this is true there is still the question of why the Remans are telepathic whilst the Romulans aren't.
So my main question is, why are Remans telepathic while Romulans aren't.
It's simple and can be attributed to a few explanations. I feel the overall ambitions and centuries of Romulan culture, values, and eventually speciation caused the loss or at least malignant telepathic abilities. This can also be why Remuns might have more active telepathic abilities as well..
Romulan culture values deception. The constant need to be deceptive and culture of secret behavior changed the wiring of the original Vulcan physiology. Or possible genetic manipulation to create a caste system.
Lack of inward meditation and mental discipline practices
Possible systemic racism and anti-telepathic violence.
Remuns inadvertently are in touch with their most primal emotions due to the inhumane way they had been enslaved. This causes more inward thinking and awareness. The constant thoughts and emotions and imagining of fighting back and getting revenge may have triggered some genetic mutation to reactivate and actually increase and enhance telepathic endowment. This was possibly one of the reasons ancient Bulcans were so violent.
Remuns (telepathic ones). Are more on par with an advanced Betazoid. Troi could not hold back Shinzons Emissary. Troi is genetically superior to most Betazoid telepathic abilities due to her mother. Even though she's only half betazoid, she is on par with a full Betazoid and is attributed abilities other full Betazoids can't tap into
(even though they are nominal or low level). It's still superior to most full Betazoids.
So Remuns might be more powerful than a Betazoid on average.