A simple statistic: Before the British showed up, Indian GDP was 15 to 20% of world GDP. When they left its was 1.5 to 3% of world GDP. Something tells me the colonial experience might have something to do with it.
Britain and the US really industrialized in the mid 1800s ( although britain loves to pretend it did in the 1700s ). Parts of europe followed soon after. Japan industrialized in the late 1800s. India ( and china ) industrialized after ww2 - india much more slowly than china due to its democratic and bureaucratic baggage. For more than 100 years, india was prevented from industrializing by britain. You can't ignore that significant opportunity cost.
Also, you are wrong when you say colonial "adventure" had nothing to do with industrialization. Excess capital and excess resources are the prerequisites for national industrialization. British industrialization was funded by opium money from china and resources from india. The need for resources is why japan and germany sought to create empires for themselves. It was a necessity to industrialize.
Having said that, I don't think you can honestly calculate the costs of colonization because there are so many factors involved. Would india have been able to follow meiji japan's or even mao's china's example and industrialize? We can say that india lost a lot due to british imperialism, but I doubt we'll ever know exactly how much. At best, it's just a guess.
But something like pre-1850s hermit kingdom Japan is another possibility. And the hermit kingdon's share of the world's pie would have declined greatly, too, with nobody to blame.
Certainly lots of cotton mills got built in the late 19th C, in both Japan and India, and all using the same off-the-shelf technology, and often the same capital. There's lots of interesting detailed work comparing them, and tracking things over the decades. And while I'm not an expert, I don't think it supports any very simple ideas of good guys / bad guys.
For example, here's a link: https://pseudoerasmus.com/2017/10/02/ijd/
Japan is a bit of an aberration. It was the only non-western country to industrialize early.
Now, India might have done so also, had it somehow avoided industrialization yet maintained contact with industrializing countries. But, a counterpoint to this is that India basically didn't industrialize after independence either. Only when the "License Raj" was done away with several decades later did India start to grow quickly. (In other words, mere absensce of colonization was not sufficient for growth)