Have you heard of TV tropes? It's a wiki of ... well, tropes in story telling (warning: for some people following a single link to https://tvtropes.org/ means they find themselves half a day later with 32 tabs open and having read up on all kind of story tropes while having forgotten what time is).

On the one hand it will help you recognize the tropes and figure out how many of them are used in all story telling (yes, even the good ones), but on the other hand it can help appreciate that it's not the tropes or the broad strokes that make up a story, but how well it's told.

There's a reason there are so many movies/stories/plays that are just re-tellings of some Shakespear play or another: it doesn't matter that the outcome is known from the start. The journey and how well it's told is what's important.

So basically: "Oh yeah, that guy's gonna betray me. I wonder how and why exactly!"

I think part of the problem is that videogame writers are almost never willing to lie to the player. Characters will mislead you by being selective about what they say, and sometimes a character is mistaken about something and unintentionally gives you false information, but I can count on one hand the times a character has deliberately fed me falsehoods.

Having been a GM for almost two decades, this has somewhat ruined being a player in p&p rpgs for me.

I joined a new long-term fantasy campaign. Me and another forever GM plus 3 rookie players.

The first adventure starts and the group gets hired by some guy to retrieve an item from a dungeon while insisting to come along with us.

Me and the other forever GM looked at each other: That dude is going to betray us and become the BBEG of this campaign!

The rookie players looked puzzled.

The GM sat there pale and grey.

Of course we were right. Dude grabbed the item, teleported away and started his reign of terror. But we just chuckled and went along with it, much to the GM's relief.

Curse your sudden but inevitable betrayal!

Ah, Lisanderoth, of course