As an Indian, I find the mention of the Gateway of India in this context odd, since it's the least egregious of the lot. Nor has there been any mainstream demand to tear it down. Locals don't treat the site with any tangible connection to the British Raj, and are at best indifferent to it. There is the plaque, but nobody seems to care.
Contrast with the Victoria Memorial, the largest memorial to any monarch anywhere, the site is replete with statues of British monarchs and Governors. Bengal as a province has the longest history of British colonialism, and probably had suffered the most of any Indian region the ills of colonialism. Despite that, there hasn't been any mainstream demand to tear the place down, or even the statues. The locals are very knowledgeable about their colonial history, but seem fine with the statues and enjoy it as a place to hang out.