I see you have posted your thoughts. I'm going to post mine initial impression before I read yours.

This one feels wonky to me. I'm not sure I'd call it the worst, but far from top tier. I don't know how to put it other than calling it barren. How is it barren? IDK, but when I tried to come up with things I really like I came up empty other than that one moment when I saw Silverstream doing her abstract art. Even for the rest of that whole sequence I didn't find much humor in. Do I hate this episode? Not sure... I'd say it's more lackluster than bad, but if there is controversy I'd imagine it has to to with the neo-tree(house) and it making the destruction of the elements episode ago feel a little cheep and without impact. Like you'd imagine for them to have at least waited. there also wasn't enough Treelight to counter or really anything answered. Just pure set up. I think too the pacing felt off. There was set up to get to the episode that took main plot way too long and it didn't feel like I had gotten to spend enough time with the main conflict.

Some other observations in no order.
1: Twilight seemed to have a pretty chill reaction to the tree of harmony suddenly being back. I'm not saying that as criticism more as curiosity. for now
2: They appear to be setting this place up as a hangout to the student 6. Interesting. I could like it as a setting especially if it has a mysterious vibe and more Treelight stuff. My concern with this season being too crowned not withstanding.
3: More time skips. I wonder how all these time skips these past 2 seasons affect the timeline?
4: Very heavy set up for them being the next elements of harmony.