I haven't downvoted you but there are a couple of problems here.
> How can anyone doing business with China look the other way on Xinjiang simply by saying "our factory isn't there".
In many industries not doing business with China is synonymous with not doing business. Many supply chains go through China, this is not something you can easily change.
Additionally capitalism incentives companies to focus on profit over ethics. You can't expect companies to act against that. That's why regulation is important to limit what companies can do to what is acceptable.
Your expectation here is just not realistic.
> Every one of us buying goods made in China is enabling their behaviour by showing that we would rather make more money or would rather have cheaper electronics and plastic crap than standing up for the human rights of the people in Xinjiang who are the focus of the CCPs genocide.
Placing blame on consumers is extremely problematic because it assumes people can make a choice here. That is not a reasonable assumption. Consumers probably don't have the necessary information about the product (and supply chain!), so they can't make an informed decision not to buy a product on this basis. Even if they had this information, they also may not have the financial means to afford making a choice on that basis.
We have effective mechanisms to define and enforce rules, it involves governments taking action through creating and enforcing laws. Putting blame on consumers ultimately shifts responsibility away from people who could do something meaningful about the problem to people who cannot.
> As a Canadian I wish our Prime Minister Justin Trudeau would more directly speak out against China's poor behaviour and offer some temporary support for businesses that would be impacted.
Trudeau merely speaking out against China, also wouldn't help. Sanctions might help and Canada is actually one of several countries that has created sanctions over the treatment of Uighurs.
I'm sure this is not your intention but effectively you're arguing for actions that have no chance of actually solving the problem. This is also a common political strategy by neoliberals who are opposed to government intervention on ideological grounds. So one might be inclined, to think that you pretend to be offended because it's unacceptable not to but don't really want it solved either.