7.1 Ending Spoilers ahead.
In trying to stall and provoke Ronova, traveller said something that made me honestly roll my eyes. It appears that Snezhnaya story really wants to put everyone's delusions and hypocrisy on full display.
Lumine called Ronova nothing but someone else's tool without free will of their own. But let's look at what's actually happened since the game began and what she/he's actually done.
Monstadt, shows up, immediately gets recruited into fighting a wind dragon on behalf of people they barely know.
Liyue, shows up, immediately gets framed, and gets recruited by Ningguang to solve the fatui problem.
Inazuma, shows up, gets immediately beseeched by Yashiro commission to help them fight the VHD. Actually says no for once, until they see Thoma's vision get taken and immediately decide to fight the Shogunate and join a rebellion.
Sumeru is the only nation where the traveller's motivations in the Archon Quest has some reasonable backing since she actually has real investment in the welfare of the people she met to try and help them.
Fontaine is the most ridiculous one. Shows up, meets a magician, gets scolded by the archon, and immediately gets roped into defending these complete strangers in court that they only met 13 minutes ago against the nation's archon, then throughout the story, the traveller was a glorified errand boy, go here, investigate that, go pretend to be furina's friend, then put her on trial.
Let's remember that in Fontaine, the traveller's behaviour was so brainless that in retrospect, they were literally working against Furina, toward the demise of Fontaine if they succeeded.
Natlan, for all its writing issues and unprecedented traveller glazing, Natlan actually has a true enemy that makes complete sense for the traveller to fight against.
Nod Krai, like Sumeru, forms a real connection between the traveller and the cast before they decide to fall into their plans.
Snezhnaya, Traveller shows up, immediately forgets all of the beef with the Fatui and all the Fatui has done under Pierro's direction, like, I don't know, what the Doctor did to Kunikuzushi under his orders. All it takes is for Ronova to try and take Paimon and Pierro going "Oh tHe dEluSiOnS aRe vOlunTarY" for the traveller to... what, go along with fighting death?
After all this, for the traveller of all people to have the gall to trash Ronova for being a tool when the traveller has since day 1 been the biggest tool in teyvat, nearly completely without agency, constantly larping as a gun that falls into some faction's lap, waiting for them to point at an enemy and pull the trigger.
Traveller is arguably the least qualified person in all of teyvat to be saying that line, since the traveller seems to basically stand for nothing, depending entirely on what the latest person they meet says to them. If the abyss manifests as a person and goes "Abyss lives matter too you know?!?!" I bet the traveller will 100% work with them too.