Yes it's very sad. Missus was watching Dead Boy Detectives on one of the streaming channels and the same thing - not one of the characters seemed to be in a "straight" relationship. I get it that in our enlightened society minorities have to be represented, racially, sexually, whatever - not a problem. But there needs to be proportion and perspective with the majority who are not from those groups.
As regards Dr Who, well fairly obvious the BBC seem to be going out of their way to exclude over 40, caucasian heterosexuals which is fine - but for god's sake, whoever you are casting needs to be able to act and you still need to tell a decent story. I'm not expecting The Expanse but what we saw last night even makes ST Discovery look good!