In the US startup world, CEO/CTO are those who built the company from scratch up, growing the company and selecting the first hundred employees up to where it is today (billions of dollars with unicorns). It's a symbol, in many ways, more than can be described in a sentence.

In large US companies, they're more a public figure and who negotiate large contracts in person and send regular emails to employees telling them they are the greatest company and the greatest employees in the world.

In French companies. CEO/CTO are basically absent, they don't exist and don't send any communication. You can ask some French workers who are the executives of their company and they probably have no idea. The startup scene being pretty weak with no unicorn, there isn't any example you could quote either, there isn't a French Zuckerberg or Elon.

If you wonder who's there for real, there's a bunch of rich folks who sponsor one another to board and executive seats of the 100 largest companies and that's about it.