No, they're too concerned with actual history to pretend the US wasn't a colonial empire.
Even if we count the 50 states as noncolonial, there are the territories that the US did own as colonies.
You could certainly ask "What if the US had even more such territories?", but pretending they didn't exist deserves to get "So, like OTL?"
I'm not saying it wasn't. Just that people understand perfectly fine the intent of the question, but need to show how smart they are and so ignore it.