sure, but what would counter that argument effectively? How would you do it? How do you say that all of the histories of all the other peoples touched by the British Empire would have actually been just fine, thank you very much. Many of lionhearted's plusses are assumed to have come from the Brits delivered as if into a vacuum. Who's to say that these plus' wouldn't've naturally developed, given enough time, or maybe in ways that don't end in millions of colonized peoples dying? All those other alternate histories are silent.

I would suggest that picking a specific example -- a whoppingly large example, in this case -- is a very good beginning of a counterargument.

Lionhearted saying "here is all the good that happened" needs to be weighed against a reasonable summation of all the good that would have happened. And a "here are all the bad things that happened" likewise should be totaled against the bad things that would have continued to happen.

They're both very, very hard positions to make briefly.