So the English just wanted to be mean to the Americans but be nice to the Canadians? Pull the other one.
Brits already had Canadians just where they wanted them, no need for any special exertions to bring Canada into line.
Americans were a very different story.
Brits wanted something from Americans, something important and were willing to do whatever necessary to get it.
What did they want?
Direct rule, for starters, with British appointed governors, but more important was taxes: Brits wanted, in effect, to collect rent from American colonists.
That's what the whole "no taxation without representation" was all about.
Read the whole list of two dozen+ items in the Declaration of Independence.
Very few, if any, apply to Canadians in the way Americans took them.
Worth noting the population of Canadians in 1775 was circa 50,000 versus nearly 3 million Americans.