Warning: this will be long but the topic is interesting.
I feel sorry for actresses like Rani and Kajol who are both younger than 40 even Aishwariya is slightly older than them.
Unfortunately though, Kajol has been appearing in movies since the age of 16 and because she started in the early 90s appearing with much older actors (i.e. SRK is 10 years older than her) we seem to think she is really old. On top of that she wasn't acting much. She has appeared with Arjun. Why can't she at least appear with Hrithik? She is younger than him.
Then we have Shahid/Rani. I felt they had really good chemistry and they looked good together. Rani isn't much older than Shahid, what's the age difference? 4 years? Rani at least is someone who can appear with the likes of Ranbir, Ranvir etc. and still pull it off, the age difference isn't much. An actress of her calibre can have chemistry with anyone now I am sure.
Then let me use an example of the above 40s like Juhi, I think with her the problem is that she has done some alternate cinema, less commercial movies so it's become difficult to see her in a commercial film with younger men but she is only 5 or so years older than actors like Hrithik, Arjun Rampal, even John Abraham.
I think the other issue is yes some may not want to act opposite younger guys and like Juhi once mentioned, she does not want to wear dresses like she used to but seems to have accepted the fate of aging actresses albeit, in her own words, does not want to play a mom, does not want to refer to someone taller than her as beta.
As for women looking older than men, Shahid, Imran, Ritesh, are all baby faced, they look young in front of most of their co-stars regardless of age.
Basically, I am fine with Aishwariya being paired opposite Varun. I am fine with older actresses working with younger guys because really, if it starts to happen people will get used to the idea, just like how we are forced to accept the 50 something actors paired opposite actresses their daughters age. It happens in Hollywood right? Sandra Bullock and Ryan Reynolds anyone? They have an age gap of 13 years but were perfect in The Proposal.
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