agreed totally.. you put my points over perfectly.. forgot to add my partner has played a lot more of these more experimental roles online - ie the rent boy, and serial killer - than he has on film.. where to the best of my recollection he usually plays people on the right side of the law.. well there was the time he played a pdo kidnapper but lets not talk about that LOL (I bingewatched 13 episodes of this in 2 days and it was quite the experience)It is a grey area and theatre gets away with a lot more experimentation than TV or films do. Just look at how many female Hamlet's we've had over the years.
There is also the business side of making these things. If you're putting millions into a production you need it to sell and be appealing. If that means putting Eddie Redmayne in the lead of The Danish Girl instead of an unknown trans actor then that's what will happen.