I left a Canadian university in 1989 without graduating because the opportunity to do a startup was more aligned with my career goals than the dated CompSci program that was preparing me only for working for government, banking or an oil company in 1970s style data processing environment.
If the startup failed I planned to go back to school elsewhere. The startup was a success though and 6 years later I found myself looking for a job. I searched in Canada but given a choice between moving 5400km and 2 timezones to Ottawa where I knew no-one to work for Corel and moving 2200km and 1 timezone to the bay area where I knew a couple of other expats and colleagues. I chose silicon valley and the bay area.
I haven't regretted this choice though I have looked casually every couple of years for opportunities in my then current field. It has never been fruitful; the opportunities just aren't there. Before I left Canada I interviewed a guy who had been on the software verification team at Intel for the 486. He was desperate to move back and was willing to take almost anything to do so. I assumed that one day I would be in the same position. I am now probably less than a decade away from retirement so my main focus now is getting over the finish line in the most efficient way possible. That probably means staying put in the bay area.
I do know that sure as fuck that I won't be retiring in the bay area though; I'd have to work 5-7 additional years to afford it. This place isn't worth that. At all. I have considered Vancouver but honestly the expense of moving to the most expensive market in Canada from one of the most expensive places in the US just to try it out is also not worth it to me. I don't know where I will end up living. Maybe Hawaii.
I do think it is essential that Canada do more to develop the domestic technology and software industry and more than just international offices for Google, Amazon, etc. Canadian universities are offering much better programs (which is part of the problem!) Entrepreneurship and access to capital has come a long way in Canada in the last 30 years and it is a lot easier to attract international talent to Canada than it was. Provincial government incentives for hiring and market development would help a lot. The federal science and technology R&D tax credits helped our startup significantly. The tax credits for export market development were inaccessible to startups and/or companies which sold intellectual property which hurt.
I follow with interest the C100 and other efforts to advance Canadian technology though I wish there was more focus on funding these efforts domestically rather than coming hat-in-hand to SV for venture capital.