I mean we did have a pretty brutal occupation of many other countries and were directly responsible for the deaths of millions of people in the process. We even had our own fair share of racist leaders - take a look at what Churchill had to say about Indian people for example. The timescales were different - Britain committed its crimes over the course of centuries rather than a decade or so - but it's not accurate to say "nothing in their history is even remotely comparable" to Nazi Germany.

The main visible difference nowadays is that Germans of today are hyper-aware of the atrocities committed in the past by their ancestors. Britons are often either ignorant of theirs or are proud of them.