I understand the want for transgender people to play a part in characters that are transgender but currently it just isn't a feasible idea. It is currently estimated that 0.3% of the US is transgender.
Being Transgender does not automatically make you a good voice actor, writer, artist or game developer. Nor should devs just hire transgender people who are worse than non transgendered people in a role, simply because they are transgendered. That would not be equality. If both candidates are equal in skill and they will be working on a transgender character, then it makes sense to hire the transgender person in some aspects.
I also think you discredit the role of voice actors a bit with this. Their entire profession relies on being able to "Get in the skin" of others, so that they can portray them. Just because they aren't transgender does not mean they can't accurately portray transgender. Pretty much any character they portray is different to themselves with different motives and feelings to any they have experienced themselves. There is nothing particularly special about transgender that makes it un-portrayable by anyone who isn't transgender. There are plenty of voice actors who have played the opposite gender convincingly, there is nothing stopping them doing the same for someone who is unsure of their gender, switched gender or is currently transitioning.They can still seek advice from transgender people.
As for the backlashes some of these characters faced. While some of it is just down to pure bigotry and always will be, I don't think all of it is. Krem is a good example. As you said during development Krem was not transgender, it was a last minute change. That to me reeks of pandering "quick shoe horn in a transgender character so we look progressive!". I cant speak for you but if I was transgender I think I would not be happy about that. Yeah it's nice to see a dev representing transgender but if they are just doing it last minute, not really thinking about the character as a transgender person. Then is that character truly transgender? On the surface Krem says all the "right" things, but you never really see past the surface. The struggles and troubles he has are the very obvious transgender ones. He is a very one dimensional character because most of his prominent character comes from a last minute decision.
The Witcher 3 again is the shoehorn problem. The game is set in an amalgamation of medieval Europe. The argument that it is fantasy and therefore should have black people anyway doesn't really work. Just because something is fantasy does not mean you throw everything about the setting out of the window. It's also indicative of a wider problem with the current progressive movement in games. People think every game should be inclusive of everyone. Rather than creating a market where different games tailored to different people can thrive more. Instead of the current market that is mostly aimed at young males. The only way a game can be inclusive of everyone is if the game is just a mirror. If Witcher included black people that criticism would just be shifted to, why aren't there Hispanic people. Then why aren't there Asian people. Why aren't there transgender people. Why aren't there ... [insert under represented minority here]. It becomes an endless loop. No game can represent everyone. Devs should be allowed to create the world they want to create. Yeah people are free to criticise but that does not mean that criticism is valid, nor does it mean that criticism should not be criticised itself. It also has to go both ways. Revolution 60 is a game that only features white females. Yet is critically lauded for doing so. I wonder if the Witcher 3 only contained black people would the same critic have criticised it for doing so or would they laud it. Revolution 60 is the sort of thing we should be advocating for, someone created the game they wanted to make, told the story they wanted to tell, that isn't all inclusive. If anything it is laser focused on being exclusive. We need to create the market where this can happen rather than push what is essentially a diversity quota. However, the same has to go for all races, sexes and genders. Even if the game was made up of only straight white men. Let people create what they want to create rather then trying to force them to make the thing you or I want to see. We don't have to like and play every single game.
Kinth's comments