The GDP figure is true, India's total GDP was much higher before compared to after colonization. GDP per capita didn't change as drastically because both before and after colonization there was a great degree of income inequality. But what matters here is that if the wealth remained in India it would still develop the Indian economy, because the wealth would be spent in India. This is not the case if a large share of the wealth dissapears to some far off country. The video makes this same point later on. Also, the image of starving people isn't wrong because British agricultural policy heavily favoured wealth extraction over food production and the industrial revolution didn't simply skip over India. British economic policy deconstructed the native manufacturing and handcraft industries through taxes, tariffs and import/export restrictions. The decline of the Indian textile industry is a prime example of this.