Why did only Akshay Kumar survive as a top lister actor when more popular stars like Sunny Deol, Sunil Shetty, and Sanjay Dutt faded who were more popular than him?

 Akshay Kumar stayed fit and stayed out of nonsense throughout his career. He had a versatile portfolio where he can do a completely comic role and also a serious action hero role.

If you see the timeline of Akshay’s movies, in the early 90s, he played mostly action oriented movies with some romance. The likes of Main Khiladi Tu Anari, Khiladiyon ka Khiladi, Mohra and Yeh Dillagi.

In between, 1997–1999 he acted in 9–10 movies which flopped. He even did cameo in Dil Toh Pagal Hai which was an out and out SRK movie. Only Dhadkan was a hit in 2000 which was a serious movie.

Starting 2000, Akshay shifted to comedy movies such as Hera Pheri, Aawara Paagal Deewana, Namastey London and the types. His market was steady from 2003 - 2010 when he did movies like Bhagam Bhag, Heyy Baby and Welcome. Most of these were mindless double meaning comedies with the combination of Paresh Rawal, Tushhar kapoor. The genre was nevertheless a hit.

His peak was the Bhool Bhulaiya, the Housefull series and Tees Maar Khan which ran just for the songs and comedy. Akshay was a bankable actor and many producers were willing to bet on him.

Compared to that, Sunny Deol and Sunil shetty can do only serious action roles. The trend of bashing up 20 people or firing guns in border faded out in mid 90s and definitely in the 2000s. Romcoms and the Khans dominated the Bollywood market from 2000 till 2012. Akshay found the sweet spot where he could do romcom and comedy which was appreciated by the Bihari, Rajasthani, UP audiences.

Sanjay Dutt was doing fine until he attempted the remake of Tamil and Telugu movies. He managed to sustain his market with the Munnabhai series but often ended up in jail due to the 1990s arms case. In my opinion, he spent more time in jail for the crime of having a weapon which he told he had to protect his family from underworld. His drug addiction also ruined his prospects. He is a good actor.

So, Akshay by switching to comedy and romcom genre when the need was there and sticking to perfection and healthy lifestyle continued to be successful well until 2015. After that, his movies have been failing except for 1 or 2 movies. In the last 3–4 years almost all his movies have failed.

What happened between Sunny Deol and Dimple Kapadia?

 Sunny Deol and Dimple Kapadia were head over heels in love. Sunny Deol debited with Betaab in 1983 which was a love story, so to create a hype for the debutante couple Amrita Singh and Sunny Deol, the news of their affair was circulated. What nobody knew at that time was that Sunny Deol was already married to Pooja/Lynda Deol whose father was a partner of Dharmendra in his motel business in London.

After the stupendous success of Betaab Sunny was flooded with offers. One of the films was Nasir Hussain’s Manzil Manzil opposite Dimple Kapadia who was making her comeback to movies after a decade of hiatus. She had also separated (though not divorced) from Rajesh Khanna. So sparks fly between them and by the end of the film they were clearly in love. But Dharmendra, who himself fell in love with Hema Malini despite being a married man, didn't allow Sunny to do the same. Manzil Manzil flopped and the news was buried.

Next, Dharmendra produced a film for Sunny titled Arjun. Dharmendra wanted Padmini Kolhapure for the film, while Sunny Deol was adamant to cast Dimple Kapadia in the film. Eventually Padmini said no to the film, and Dimple was cast. But Dharmendra didn't like the closeness between the two and warned them to stay away from each other. Arjun was also a success, and the pair went on to do many films together like Aag ka Gola, Gunah, Narsimha but barring Narsimha (that too was a moderate grosser) the films didn't work, but they enjoyed staying together. They also shared a steaming kiss in Aag ka Gola. Dharmendra was so offended by this that he kept a kissing scene with Dimple Kapadia in the film Dushman Devta.

Eventually Sunny Deol, being an obedient son, didn't marry Dimple Kapadia and everybody thought the relationship is over. However a few years ago, an image resurfaced and their romance was once again in focus. Rumours also said that when Sunny Deol faced a financial crisis and struggled to save his bungalow over a debt of 60 crores (due to failure for their productions Pal Pal Dil ke Paas and Yamla Pagla Deewana Phir Se), it was Dimple’s son in law Akshay Kumar who helped him financially to get out of the crisis.

The two actors have not acknowledged their relationship in public but there are lot of hints thrown at different points.

They were seen together in public in more than one occasion most popularly in London. In 2006, 22 years after they were first rumored to be dating, Sunny’s co-star Amisha Patel was asked if Sunny was at her on-set birthday party, and she casually said no, of course not, because “Dimple Ma’am’s” birthday was the day before, so he had to be with her. In 2017, 33 years after their rumored relationship started, they were spotted by a fan sitting in a bus stop in London, casually holding hands.