So from what I read here it seems much less of an issue if you already did sufficient research on the oaths, what they stand for, and what they stand against. Possibly even to an extend where breaking oath via dialogue can be completely avoided and even shifting to the opposite. So you have situations you could break your oath in an interesting way in but the game does not give you the option to. The only question you are asking here is why an inexperienced player isn't given clues on this, since the paladin would obviously know about their oath. Although the power comes still from the oath itself, which in my opinion can still take almost any form since it's almost literally just a pretty word for commitment. After all reasons for taking an oath can vary as much as ones for breaking it.
What really remains is weird ruling for combat, especially in multiplayer when others roleplay conflicting alignments. Let me give you an example some of you might have experienced already:
The Warlock runs ahead into the Blighted Village. The ambush triggers - but he successfully intimidates the goblin and avoids combat. So far the paladin player had no influence on any of this. Now another player or even the paladin themselves might decide it would still be best to kill the goblins. After all from what you gathered so far, they destroyed a village and now lay ambush on every traveler to visit the place. What an honorable deed it would be to prevent this from happening ever again. Wouldn't it be?
The game rules no: Your oath is now broken. That is frustrating if you were planning on staying on the right path, even more so when you had no influence on either the dialogue or the initiation of combat. The EA puts you in more, very similar situations and almost every time the game rules villains into the same category as innocent civilians if the party chose the non-violent option on first contact.
If you just don't bring a paladin, you can murderhobo your way through most places without being shunned by other factions with moral codes, which makes this circumstance even more artificial for me. And if you choose violence right away, it might be more conform with your oath than reasoning first. But you never know that for sure until you try.
