Even with assistance Traveler deals with world quest threats alone.
Even with something to help them beat the boss like sword of Narzissenkreuz they still fight alone. More people should pay attention to world quest. The philosophy of we need to make enemies progressively stronger than Traveler so that the 5 star can shine otherwise shouldn't always be done.
then again I doubt genshin players know the difference between the boss being made strong so that characters can shine Columbina, Nahida and Neuvillette can shine and now we have Ronova so that Tsaritsa can shine and Traveler being weak arent the same.
you can argue it's about stakes however an opponent relative to or not strong as Traveler can still be made the main threat of archon quest or rather secondary antagonist. Which genshin kinda did with Signora and Childe.
Traveler not being able to solona specific enemy somehow puts them a tier below where they are supposed to be in some players minds