I think there is a Canadian tendency avoid risk. With the tech sector this means that if government funding is not immediately available, nothing is worth risking your own money.
I'm reminded of one my history professors who used to say that the American dream was to start your own company and become wealthy. In contrast, the Canadian dream is to become a civil servant.
There are exceptions of course but most of these people go to the US. It isn't just in the tech sector either. Look at the number of Canadian actors or singers that go the the US.