The Lack of Disabled Actors

I would like to just ask this question to anyone who knows, who can tell me about this. So, I'm a big movie man, and a big series, TV series man. I love watching TV series and movies, but I noticed there's not so much disabled actors in movies or series. There's a couple, but not many. I know when it comes to series and TV dramas, there's a drama called Emmerdale, and I think there's two real disabled actors in that. And when it comes to Breaking Bad, the iconic TV series, there is a disabled actor who has CP in real life. But apart from that, there's not many disabled actors being starred in big movies. If anyone can tell me why this is a bit wrong in my opinion, because they have all actors of all different backgrounds, black actors, white actors, Chinese actors, African actors. But when it comes to disabled actors, we don't seem to get noticed. I think that's a bit wrong to be honest.