If your goal is to make things better, wouldn’t you be best positioned to do that in your own community? Moving to a new place with its own unique set of problems is challenging enough as it is. To hope to make a difference there is going to involve learning about local issues. Unless you mean something more generic, like volunteering in soup kitchens, homeless shelters, literacy programs, etc. which are everywhere and always can use extra help.

I’d assumed that people worried about fallout from the US election are worried more about their own situation: their rights and freedoms, personal safety, and economic situation. Moving to Canada could definitely improve some of those issues while exacerbating others. Housing in Canada (especially in big cities like Toronto and Vancouver, but not at all limited to those cities) is generally much less affordable than the U.S. outside of the big cities there (New York, San Francisco, LA, Seattle). Many people who move here find it very challenging unless they already have a bunch of wealth saved up.