Doesn't the existence - and lack of adoption - for Ecosia and similar services suggest that Europe cannot easily build FAANG overnight?

Technically, we can do it.

But unless we go the Chinese route of blocking US vendors, a lot of people will always flock to the better product that has the bigger marketing budget. And there I do not see how Ecosia could compete with Google, Xing with LinkedIn, Mistral with OpenAI, OHV/IONOS with AWS, or Hetzner with GCP.