But not everyone has that attitude. Indeed it would appear to be fairly uncommon in this country. The English settling in the Americas, Australia, New Zealand, India and Africa mostly carried on speaking English, both when they became the majority and when they remained the minority. The Anglo-Normans settling in Ireland in the 12th century mostly ended up speaking Irish, but the later plantation initiated by Cromwell imposed their own language. The English wine trading communities in Porto and Madeira still speak English, set their children to English public schools, etc. A lot of English retirees to Spain seem to carry on speaking English.

Just as those examples exist, it is hardly surprising that there are some in the other direction.