The Thrill (Spoilers)

[Kykeon]

IMHO, it's the other way round.
Supernatural influence is suppressing his natural reaction to battle.
The visions are changing him to think outside the eternal rat-race thinking of his culture.

[Stormblessed]

Possible. But he can still fight to protect himself and others. It's just that he no longer feels a thrill at slaughtering multitudes. To me his becoming more human, less animal.

[Morsker]

I figured the "Ten Deaths" were the Vorin version of the Seven Deadly Sins. Kabsal mentions some other "Ten" things on page 634 withing going into detail, so it sounds like the religion has a lot of them:

"An unpopular part. People prefer to hear about the Ten Divine Attributes or the Ten Human Failings. We accommodate them because we, also, prefer that to the deep past."

Even on this interpretation, the Trill could be one of their sins, but I rather expected the Thrill is part of Vorinism, and a masculine ideal. The religion considers being a solider to be the highest Calling.

[Xavien]

Cultural is possible, but it could also be genealogical or even trained (possibly due to your Calling?).  I always took it as being similar to Shallan's Memory where it is an actual ability.  Dalinar's comes out when he is fighting and gives him extra strength/speed/clarity though he doesn't have conscious control of it, while for Shallan it is something she has to consciously use.

[ErikHolmes]

Something blew against him. “Wait!” Kaladin said. “Why is there so much war? Must we always fight?” He wasn’t sure why he asked. The questions simply came out.
The storm rumbled, like a thoughtful aged father. The face vanished, shattering into droplets of water.
More softly, the voice answered, ODIUM REIGNS.

And how does Odium Reign? He reigns Because:

the Thrill—the enjoyment and longing for war—was part of what drove the Alethi as a people

Rayse is a drug dealer. The Alethi are his addicts and The Thrill is the drug.

I think the Radiants knew this, which is why the one tells Dalinar that if he has a desire to fight he needs to come to them and get training, so that the thrill doesn't consume him.