Thank you so much for the link! I've been trying to find it b4 but to no avail.
Your points are correct, in my case as well. Abystigma did bring a lot of players! The revenue that happened in that patch is super great, compared to Kuro's usual revenue percentage. Plus, Lee out of the spotlight for a while did bring a lot of hype when he was announced having a new frame in CN. Him being one of the main trio did contribute for the popularity/revenue, just as you stated. Although, I think Karenina is quite popular, I might be wrong though.
If recent Alpha patch can be used as a comparison, there are some differences to keep in mind.
For one, on when these patches was released. Alpha is released as part of 3rd anniversary of the game + CNY, thus in this patch, Bianca's skin, Alpha's (collab) skin, as well as Karenina's skin are all SFX and will be at this patch (Resale of the previous coating can be counted as well) compared to Lee's patch wherein Lee was released before 3rd anniv (Ayla's patch) received a non-sfx skin and Chrome having sfx skin. EDIT: I forgot, but Lucia also had a rerun of summer skin gacha, if this helps that the Lee patch gain some revenue.
Secondly, Bianca's gacha skin. The gacha, in particular, have a lot as a reward. Skin + exlcusive BG + BGM + others, and considering the fact that Bianca is very popular, it's no doubt that the patch will gain more revenue. (I forgot how much RC you decided to get just the skin, though) Chrome's sfx skin, however, is sold at the usual price (168 + 28 RC). Also compared to Lucia's gacha skin, Bianca's much more expensive.