I learnt ML, sensor stuff, R, python and all other stuff in my first job right out of school. Made easy six figures (+ benefits and hefty bonuses) without any recruiter haggling, and am in comfortable position now. Because I turned towards traditional engineering companies, and then went there and did what I wanted to do as I got an understanding and tech oriented manager. I changed a lot of internal workings in that company.
Exchange can be normalized for most us/ca comparisions, i.e. 100K in Canada is only 70K US but most prices are normalized for that.
The Bay Area is mind-boggling expensive though - and you'd all be naive to not consider that.
My flat in Montreal would be $5500 a month, USD anywhere in SF. It's amazing. And cheap.
Also consider that startups in the US have to cover healthcare, which is very expensive. That said, if you have healthcare in the US, it's better than in Canada. Again, it doesn't really matter for normal people under the age of 30.