In the same way business schools are really networks or clubs (there is little learning taking place at BS..), ENA is a club for the highest-ranking civil servants in the country (i.e. no learning happens at ENA/INSP, merely co-opting into the club of those who then should serve the country but instead gut the state for the benefit of their class).

I believe it's more likely for a professional engineer to be liable, but surely in projects of any reasonably large scale there would be several layers of engineering management and oversight such that the engineer working on a part of the puzzle wouldn't be liable for a greater architectural flaw...?

For example, the Boeing 737 MAX had a high level fatal flaw that existed because of a mismatched collection of arguably correct or valid hardware and software systems. The engineers who designed the more forward set engines probably did their jobs correctly, and the software "engineers" who built the pitch up correction software presumably didn't write bugs. However, the combination of the two were primary factors in the fatal accidents.

I think that's a bit harder to replace than it is to clean a dirty toilet. Presumably the professional engineers can clean their own toilet if absolutely necessary.

The key is that if it requires some sort of certification, as Canada claims it does, then it should be a modifier/adjective on the title like "certified janitor" or "licensed engineer".

Just claiming an existing single common noun as an exclusive term belonging to your organization is clearly an untenable position. If you have to keep reminding everyone that they're infringing on your trademark all the time by using a common word, you've already lost.

A long time ago in Paris the street sweepers were euphemistically called "surface engineering technicians" (paraphrasing from the French "technicien de surface", but I think this is close enough)...