Moreover, do we know of any examples of Anglo-Indians staying after independence? Did any achieve prominence in post-colonial society?
There really was not much reason to stay on. Life in a British cantonment in India was rather insular. Behind the high walls and well defended ramparts, the ethnically British population had little opportunity or desire to form attachments with the locals, other than to maintain political and/or business ties with the local elite. Memories of the Mutiny, contemporary protests and general strikes, these had left the British wary of the local population. The cantonment was a world unto itself, and one where British folks stationed in India mixed with one another, and few locals. On the eve of Indian Independence, the cantonment system as well as the extralegal protections and privileges granted to British folks residing in India were kaput.
Although depending upon ones job, there was an opportunity to stay on.
I’ll explain. Generous pensions and benefits were extended to old India hands to relocate to the UK. In some cases, the value of the pension was roughly equivalent to what a UK based medical doctor would earn. And so a comfortable upper middle class existence awaited some back in the UK. And for those still wishing to serve the empire, there were transfer options available throughout Africa. Not surprisingly, many took these offers. Without much attachment to an India without a cantonment system and extralegal privileges, being paid to head home to the metropole was too good to pass up.
But the new governments of India and Pakistan were even more generous to certain British civil servants. The tax men! The new ‘kings’ wanted to know what was in their kingdom, what assets it’s land and people possessed. How much they could squeeze out of them to cover the costs of government. And a few British civil servants in the revenue departments were ideally positioned to assist in that regard.
Looking back to find an older post I made and will add some additional information and a citation when I locate it.
A good discussion about it here from a few years back when it was fresher in my mind. And a great comment from another high quality poster who has some additional information and sources.