If I had to say I am actually not a fan of forced changes or forced plots. For example, I never liked when someone was fired from a show and that character just died and suddenly got replaced just to keep the balance.
A forced change or a forced plot can actually create the opposite effect of what it was intended by the author.
An example, of a forced plot that ruined a story would be "The Abandoned Empress". It is a korean novel in which the ML killed the MC's child and raped her among other things, thus when she returned to the past she had a huge trauma. The author tried to sweep everything under the rug by saying the ML of the present is a different ML from the alternate future.
Beleive it or not forced topics are not unique. In "Doctor Elise" the MC wanted to break her engagement and she succeeded but the author forced the engagement to continue with a silly explanation just that she could continue to be in contact with the ML.
There are also examples of forced plots due to authors wanting to overextend their abilities of writing. Trying to be inclusive in every way they can. An example of this being by Inori the author of "I'm in love with the villainess". The story started out great and it had a very interesting theme. It slowly started to include elements and characters that felt forced. One of those characters created a plot hole.
The heroine needed a love rival besides the Crown Prince so they added the female cousin of the FL to compete with the MC for the love of the FL. The problem is, that according to the original story, when the MC hadn't possesed the heroine the female cousin showed no interest in the FL. Even when the FL was engaged with a douche of a Crown Prince. The author didn't really concentrate on the story and they started concentrating on inclusion of multiple topics that didn't really add anything to the story.
The author even went as far as introducing an incest couple of a blood related brother and sister into the mix. They tried to kill everyone but even after getting stopped they still got financial support by the MC just because the female used to be a maid of the FL.
What the author did right was showing the struggles of a prince in the main cast. In which they felt better and more liberated by being a woman instead of a man (a whole curse was involved).
What they didn't do right however, was trying to include as many problems as posible at once instead of giving each struggle the correct amount of screentime in order to let the reader get more involved with the story. What do I mean?
There were multiple things going on throughout the story at the same time. So much so, that when it was time to talk about the MC's past you were never able to identify with her or even feel empathy for a trans bully that comitted suicide.
Suicides are a serious topic but when you just gloss things over like "I got bullied, got betrayed by friends, and years later I met my ex-bully. Ooh yeah did I forget to mention the ex-bully comitted suicide? My bad." My point being the author wrote so many things going on that when a serious topic arised you couldn't really feel any empathy towards the situation.
There are also cases in which the anime and manga are bad but the novel just doesn't get justice like the recent anime of "The Magical Revolution of the Reincarnated Princess and the Genius Young Lady"
Now that I have mentioned bad examples of what some authors have done, let's mention some examples in which the creators did a great job.
A recent original anime that added LGBT representation while not feeling like that was their only trait was "Lycoris Recoil". Nothing felt forced and the characters added so much more to the story. They didn't have only one trait that defined them.
A good cartoon series that changed the original characters was "She-ra and the Princess of power".
It was a great series (and I will never get tired of saying it) in which each character was unique but nothing felt forced. I loved the whole story and representation was just the extra flavoring, it wasn't the main course.
As I see it, representation can go good or bad but it mostly depends on how well written a story is. The same thing goes for changing a well known character be it their physical characteristics or their sexuality. It can go good or bad depending on how well written said changes are done.