I don't really hold any stake in the whole Genshin VS HSR thing since I've never played the latter to begin with but as someone who didn't start playing this game until Natlan I can certainly tell you there are times where I've felt like the game deliberately treats me as a secondary citizen just because I happened to join the game at a later date
Almost a third, probably even more, of the game's cast basically don't exist in my playthrough outside of single-scene cameos since I've missed all of their past events and their periods of gameplay relevance where I might have been exposed through them through in-game stories or by seeing other people in the playerbase talk about the latest released characters
Doing the new Mondstadt quest and just being given a still photo with like five sentences of text inadequately summarising events instead of letting me experience them directly, not letting me get the old weapons from past events, chronicle wish costing the same as a regular banner even though the entire concept feels like them slapping a clearance sale sticker on the oldest characters and so on... Even if they're mostly minor things that can be ignored since they don't effect current events beyond the story it still feels as if the game's telling me to not even bother getting invested