One thing that I have noticed that, many Indian Bengalis underappreciate their city compared to cities in western and Southern India. But when I look at statistics I can see that Kolkata still has 3rd largest economy in India right after Delhi and Mumbai. Still has 3rd largest number of Dollar millionaire among the Indian cities. When I look at city infrastructure, I do not see much difference between Kolkata and top rated Mumbai or Bangaluru(Delhi is much ahead with it's 400 km Metro rail and wide expressways, so I will not compare it with kolkata). Infact Kolkata have many advantages compared to those cities. kolkata's suburban rail network is the biggest in India and more than 3 times larger than much touted Mumbai suburban railway. which has 2nd largest network. Bangaluru or other cities even do not come into comparison in suburban rail netwok. This is not a small feat.
Kolkata's traffic management and varieties of transport are better than other major cities. Kolkata's metrorail is the most efficient among the Indian Metros if we compare the passenger per km. Kolkata's road condition and width is at least at per with Mumbai and Bengaluru from what I have seen from Youtube. kolkata has some of the top rated Universities(Calcutta Uni, Jadavpur Uni.) and other educational institutes in India. Only perhaps Mumbai and Delhi have comparable number of Educational facilities. For touristic visits I can not find anything comparable to Victoria Memorial or Eco Park in other major Indian cities. Kolkata New town is one of the biggest, developed, beautiful and planned satellite town in India right now.
The only drawback I see in Kolkata is the lack of job opportunities for highly educated urban youth. But Kolkata is much bigger if you consider jobs in MSME sector which is a big part of economy for a large city. For the last few years, Kolkata's growth in IT sector and overall infrastructure is impressive.
It is true Kolkata used to be the top in the league, but even after Indian Central govt. discriminatory policies in 1950s and 1960s which hurt Kolkata and West Bengal in general and later 34 years long communist rule and their destructive economic policies, Kolkata still among the top three. This is not a small feat. Indian Bengalis should look forward to achieve the top spot again in the next few decades rather that lamenting the past mistake which I see much often in varous forum.