Your point about OVH still falls flat for a US audience, unless saving a few dollars is a critical concern.
$20 for 4gb of ram, 4tb of bandwidth and 2 cpus at Linode is a rip-off? I guess if someone were quite lacking in funds and needed the absolute most cut-rate VPS prices they can get, it might be viewed as a rip-off. That's a legitimate issue if so, sure. By all counts Linode in fact provides a tremendous service at a low cost, as with DigitalOcean. I'm guessing that for most people, $3 vs $7 (or a similar ratio) simply doesn't matter very much, especially when you consider laws and latency.
To compete fully, Scaleaway and OVH will eventually need multiple US data centers, otherwise the price gap by itself isn't going to be enough and the world's largest economy will remain the domain of DO/Linode/Amazon/etc. Those companies already know they'll have to charge more for service in the US, which is why they don't already have lots of US data centers after all these years, they have no competitive advantage to bring to the table.
Again, if you locate in Canada you're opening yourself up to multiple jurisdiction compliance. You're going to have to comply with both Canadian and US laws in that case if you're a US business. The complexity and burden of doing so will only continue to expand.
Saving a few dollars by locating with OVH in Canada might be fine if you're just running a test setup and have no intentions of running a real business on it.