How has the Indian Institute of Technology, Madras (IIT-M) enhanced the reputation of Chennai as one of the premier cities in India?

To answer your question in the most simplified manner, I would target the primary factors which are as follows:

• IIT Madras happened to be one of the oldest institutes in the city. This is the centre of attraction and it is a big deal for students.
• A city like Chennai is a good place to relax and unwind. From any sort of historical, spiritual location to even recreational ones, which include - Mahabalipuram, MGR Memorial, Pondicherry are certain places that can help you bounce back in life.
• The food can be a little tough to get adjusted to. But don't stick to the college canteen or mess, go out and experiment. It will help break the monotony of life.
• Chennai, as a city is excellent for women too as it is safe for them to reside in and explore ahead.

This is what makes this city even better for others to love. This is how the presence of an IIT can change the way people look at the city.