[MANGA SPOILERS] About the new episode...

Why did they show so much so early? As though the visuals in this season's ending don't show enough, now we see so much of Marley?

Anime-onlys who like to analyse and theorise will probably be able to piece together stuff like that there are people outside the walls and the advanced stuff there (note that she said she was a titan for 60 years, this means that the world outside the walls has had guns for at least 60 years and likely now has better technology, which Marley does) and the fact that they turned people into titans.

And also, a lot of stuff can be infered from the series so far if you look into everything. For example, the syringes used by Marley to turn people into mindless titans and the syringes used by Grisha on Eren, this could imply that Grisha is also from outside the walls, and from the syringes and what he said you can infer that Eren was turned into a mindless titan and it's also implied (I've seen some people in the anime-only thread guessing this) that they turn back into humans but also titan shifters when they eat another titan shifter, and using this they could guess that Eren ate a titan shifter, and who could that have been?

I may be overestimating how much it gives away because I've already read the manga, but a few of the people who analyse it and make theories with dedication might come to some of these conclusions, and this is stuff meant to be revealed a lot later in the Uprising Arc and even in the basement reveal. Why has a scene like this been put so early in the anime?