The traditional TV cookery show is disappearing. Yes, there's a few of the longer lasting 'big dogs' with long careers in hospitality around, but you hardly get any new shows. And there's not as many of the traditional stand around chatting and cooking shows, used to be the schedules were full of them. The only new kid on the block I can think of is Big Zuu and until recently his shows were on slightly more niche channels.
I think not only have broadcasters cut them because they cost more, but viewers aren't as interested in them, they are old fashioned. All the new, modern chefs and bakers who might have had shows in the past are on insta and tick-tock.
I'm not sure Nadiya would get a show at all if she won today. I don't think I ever watched a Nadiya show, but I haven't watched any cookery shows lately, not even Mary Berry when she did her Christmas stuff and definitely not Jamie Oliver. Used to be everyone watched them.
I can't say whether the BBC were racist or Nadiya's career came to a natural end. Maybe it's a little from column A and a little from column B.
In other posters defence I would say that autocorrect is VERY determined to spell her name 'wrong'.