I don't think that's an alternative to US hyperscalers. Scaleway is the closest thing there is. Replacing a single service with 10 others is not really an alternative in my opinion.
Isn't the whole point of Cloudflare's Workers to pay per function? If it is self-hosted, you must dedicate hardware in advance, even if it's rented in the cloud.
I get the point. But those are incomparable. Hyperscalers don't compete on price, they compete on scale and services offered. The compliance, the security, the support, the integrations, the backups.
Can you host your own object storage open source software, key vault OSS, VPN, queue service, container registry, logging, host your own Postgres/MySQL? Sure, but you will need to research what is best, what is supported, keep it maintained, make sure to update it and that those updates don't break anything, wake up in the middle of the night when it breaks, make sure it's secure. And you would still need to handle access control across those services. And you would still need a 3rd party service for DDoS protection, likely CDN too. And you would likely need some identity provider.