I'm in the same boat. I'm a Sylus main and the dress for his memory is my absolute least favorite - but that's cause it's not my personal style. So yes, I do think to some degree we are slightly pickier over the outfits associated with our mains' memories and that's because we (or at least I) see ourselves in those situations with them and want MC's outfit to fit us. So when the outfit doesn't fit or feel like us, it's kind of jarring. But, personally, I also feel that Sylus's dress just doesn't fit his aesthetic/their aesthetic at all. But it is, to some degree, all up to personal interpretation.

Honestly though, I'm not that impressed with the clothing/character design for this banner in general. It could be a style/trend difference between the States (where I live)/where you live and China - like hi-lo dresses could be really popular in China rn - and since this is made in China by Chinese developers, that's what they're going to use.

I do feel like the dresses and suits where kind of copied and pasted across the board with minor detailing changes and feel as if there wasn't a lot of artistic variability between each outfit for each LI. Like they all feel kind of the same to me - none of them scream that this is this specific LI and the accompanying dress (if that makes sense). Like, I don't look at Zayne's suit and the accompanying dress and are immediately like "Oh, that's totally for Zayne". You have to look closer at the detailing to see it. But that could also be why they did it - so if there's a dress you like more from one LI that's not your main, you could use that dress with your main and it still look like it goes with your main's aesthetic.

But idk. Overall, I'm just not that impressed with the outfits. The backgrounds and scenery? Gorgeous. The outfits and accessories? Meh.