So this is going to (probably) be an unpopular opinion but here it goes:
While I understand Jewish people have a long and continued history of being discriminated against, I believe it is incorrect to compare Mrs. Maisel not being played by a jewish actor with a trans character being played by a cis actor or even with representation concerns in Hollywood more generally.
1. Jewish people may be discriminated against but it would be difficult to make the case that they are an underrepresented population in Hollywood. There are many, many very good Jewish actors, directors, producers, etc.
2. There are many, many Jewish roles in fiction. It is not uncommon watch a show or a film that has a character who is Jewish. Maybe not every show has a Jewish character, but again, I would not exactly consider them underrepresented, in the same way as POC, trans, lgbtq, etc.
3. Jewish characters are not necessarily defined by their Jewishness. They are (usually) allowed to develop as people beyond the one specific experience of being Jewish. This is not something that can be said about the majority of trans characters. And when the whole character arc is based on this one defining (highly stigmatized, highly opposed, highly specific) trait, it feels improbably someone who has not had that lived experience can accurate portray that kind of role. This is not to say there are not certain experiences that are specific to the Jewish experience, but when the story is not entirely Being Jewish(tm), that experience is less central and thus it is less important (to the storytelling) for the actor to also be Jewish.
4. Jewish actors are not confined to playing Jewish roles. If a Jewish actor doesn’t get a Jewish role, there are many other opportunities for that person to get a job. This is not the case for other minorities. If Scarlett Johansson takes the one trans role (again bc there are not a lot of them), she is taking that from a trans actor who more likely than not, will not be able to find another job playing a non-trans character. Trans characters are the one place trans actors are given in Hollywood and it is a small place. Again, this is not the case for Jewish actors.
