Oh, to be clear, Canada has the technology to develop a vaccine. Maybe a bit slower than a superpower, but the knowledge is here.What else you gonna do, EU restricting exports, Chinese one is argueably useless, Russians can't supply their one in enough quanties.
And only a relative few countries could manufacture the vaccines very few can develop one mostly EU/USA and Russia.
We where working with China of all places to finish and manufacture one. They cut off contact, and took the research. It was worth a shot, I suppose. (Currently, Canada is having a diplomatic spat with China over a little thing of an extradition treaty with the USA; but the shut down of contact was probably mostly vaccine nationalism here.)
It just lacks the ability to manufacture it in any quantities. 10 years ago it could have, but today, it isn't practical.
Canada is a strange country. It has the technology and materials to make nuclear bombs, but does not out of principle. (One of the problems with the CANDU reactor design is that it can be "easily" modified to make weapons grade fissionables. Oops.) Also, Canada isn't very good at rocketry. And moose don't carry bombs far.
If, say, even the flu vaccines Canada uses where made in country, retooling that to produce a AZ could have been viable, and the national security threat of vaccine hording wouldn't have been a problem. (Not mRNA; mRNA is new tech, but in under 10 years I suspect flu vaccines may be made using mRNA tech)