@bold - I have definitely seen that happening in the few posts that I have created or tried to interact in. Post leap, people were more open to discussing both couples and so, it was possible to discuss the story arc but not anymore. As you said, people's feelings are heavily invested in a couple of their choice.
I have mentioned this in another post also that I have become like a brand ambassador of the KuKu AT because I keep advertising it to people to come and share their views and opinions. There are a whole bunch of people on that AT who like discussing the story and characters but as the name suggests, it's more KuKu centric. We do discuss the overall arc most of the time but most of the participants have stopped posting on the forum because of the backlash from emotionally invested fans. People seem to just want to discuss one couple and no other character so most of them just stick to the AT. Since I am still pretty new to the forum, I try making posts covering as many characters as possible but it does feel like I will stop doing that pretty soon.
I'll attach a link to an old thread here. I think you will find the discussion interesting.
https://www.indiaforums.com/forum/yeh-rishtey-hai-pyaar-ke/5143094/too-mera-nanko-nahi-ho-sakta
This forum actually has quite decent, smart and reasonably balanced members - comparatively. And imho far more open minded than other forums/SNS sites.
Having said that, everyone has their favorites and of course, strong opinions. I have been on this forum for a long time and I do agree, some come across as very harsh, but relatively most members try to reason peacefully.
MishBir fans in general do not have any problem with makers showing KuKu story, but since MishBir are the leads their fans somewhat feel entitled and get edgy when AM story is compromised to accommodate other stories/tracks. I feel most MishBir fans are not naive to just want to see AM romance all the time even if there is no story... in fact, when AM story is done justice and given it's due screenspace, fans actually enjoy all the other parallel tracks and the show story in general. It's when the balance is off, that's when things and emotions go out of control and we see sparks flying...
And lately, our show writers/editors are not at their best, they have lost the balance and made a khichadi of the show trying to show too many things at the same time and as a result not doing justice to any couple, track or character! They seem to be in some kind of rush... God knows why! It appears as if they have a goal to nowhere...
They could have easily covered KuKu wedding in one episode and MishBir wedding in another... both sets of fans would have enjoyed it much better that way! For MishBir fans, this was their leads first shaadi and they have been waiting for the past 11 months. But what do they get, parallel shaadi and that too in micro bursts, with main focus on Kuhu's emotions... fans bound to get upset!
And not to mention their obsession with showing parallel scenes of the couples! Haldi sequence was still reasonably done, but there have been songs and scenes in the past where the focus kept jumping from one couple to another and the viewers are at a loss because the two couples are in a different stages of their relationships and viewers have to constantly keep switching their emotions to keep up with what they are showing!
CVs need to practice what they preach - #KeepItSeparate
Regarding the ATs, ultimately we have ATs because we are a fan of a character or a couple. The story being discussed or mega analysis done in the ATs is also from the AT subject point of view only - so it doesn't really cover the story of the show in it's entirety anyway. And it is very hard to be neutral in the ATs because the members there are clearly a fan of one subject more than the other! So one cannot help but have a biased opinion in any AT!
The major difference between the two couples fans here is that MishBir fans have to work less hard at selling their couple than KuKu fans do since the show has explored MishBir emotions way more than KuKu. Also, with Kuhu's character flipping constantly, her fans have to go to great lengths to justify her character and actions and give it a positive spin!
I suspect the reason for the backlash that you have mentioned in your post is a result of the way grey characters like Kuhu and even darker Meenu are defended in some posts with logic that comes across as twisted and convoluted and that too for the character's very obvious plotting/selfish actions! Trying to present the character's obviously hurtful and deliberate actions as something meaningful, by hook or by crook, and at the same time presenting A/M's very obvious positive actions also as some deep hidden convenient shortcuts is not something that most people will buy into and they retaliate. It's not like AM fans are superficial and are not capable of understanding the story and it's layers or lack in intelligence but at the same time they are not going to accept arguments that come across as twisted attempt to present AM as someone they are not because AM fans also watch the same show and can clearly see what's happening.
Also, some fans have made it clear in their posts that Mishti rubbed them the wrong way early on, so they have made up their minds that they are not going to like her... then it's hard to take their opinion as neutral, isn't it?
Since Kuhu is a grey character and I am not her die-hard fan, my opinion on her character is situation based. But I haven't made up my mind that I am not going to like her... so my opinions have some room for adjustment.
I have expressed my view on Kuhu as a MishBir fan, in this post: https://www.indiaforums.com/forum/yeh-rishtey-hai-pyaar-ke/5152284/kuhu-is-still-annoying-and-mean
Sorry bahot jyada lamba ho gaya... didn't meant to write a long essay I guess I had a lot to cover!
Btw, you make all kinds of different posts in the forum and I appreciate your efforts in keeping the forum interesting 👍🏼